Acta Physiologica Hungarica

Published by Akadémiai Kiadó
Online ISSN: 0231-424X
Publications
Article
CFY strain rats (both sexes, 180-210 g) were fasted for 24 hr. Several anticholinergic agents atropine, oxyphencyclimine, propantheline, trantheline, hexocyclium) were administered (i.p.) in equimolar doses (28.78 nM X kg-1), and to compared to the cyto-protective effect of atropine sulfate (0.01 mg X kg-1). Their effects were studied in (1) one hour pylorus-ligated rats, being given when the surgical procedure had just finished: volume and acid output were measured; (2) the gastric mucosal lesions induced by 0.6 M HCl. Drugs were applied 30 min before the administration of HCl (1 ml, i.g.). Rats were killed 1 hr later and the number and severity of lesions were calculated. We found that (1) atropine, oxyphencyclimine, and propantheline did not significantly decrease acid secretion, while trantheline and hexocyclium inhibited acid output; (2) all drugs provided significant protection against the gastric damage induced by HCl; (3) no significant difference was found in the extent of protection produced by the different drugs in the HCl-model. We conclude that atropine, oxyphencyclimine, and propantheline are gastric cytoprotective agents.
 
Article
The effects of different doses (0.01-0.1-1.0-10.0/mg/kg-1) of beta-carotene were studied on gastric secretory responses of 4 hr pylorus-ligated rats: development of gastric mucosal damage (as assessed by number and severity of lesions) produced by intragastric administration of 0.6 M HCl; tissue level of adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), adenylate pool (ATP + ADP + AMP), ratio of ATP X ADP-1, "energy charge" (ATP + 0.5 ADP X X (ATP + ADP + AMP)-1) (during the development of gastric mucosal damage by 0.6 M HCl and of gastric cytoprotection by beta-carotene. It was found that beta-carotene did not decrease the gastric secretory responses of 4 hr pylorus-ligated rats; The development of gastric mucosal damage could be decreased dose-dependently by the administration of beta-carotene; the ATP transformation could be decreased by beta-carotene; the tissue levels of cAMP and AMP could be increased significantly and dose-dependently by beta-carotene; the ratio of ATP X ADP-1 could be increased significantly and dose-dependently by beta-carotene; the values of adenylate pool and "energy charge" remained unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)
 
Article
In this study the myosin preparations isolated from E. Coli cell cultures were analysed. The isolation of myosin from fresh cultures resulted in a substantially higher (approximately 10-fold) yield than from stored cells. The coli myosin, despite the two DEAE-cellulose treatments, contained more RNA and P-lipid than the myosin prepared from skeletal muscle. The RNA content can be removed gradually by acetone denaturation and lipid removal followed by subsequent washings. The fresh preparations contained protein-bound alkali-stable P; part of this was released by Cu ions. The coli myosin can be phosphorylated. The phosphate uptake depended on the concentrations of ATP and Mg2+ and on the time of incubation. The alkaline hydrolysate of the phosphorylated, washed lipid-free preparation was resolved into 8 P-containing peaks on ion-exchange chromatography. Of fractions P-Arg, Pi, P-Lys and 2 P-His conformer were identified by means of synthetic compounds, elution pattern and specific reactions. The remaining compounds could not be identified. The most abundant component was P-Arg suggesting that this compound might play an important role in the cytokinetic movements of E. coli.
 
Article
The cytoprotective effect of different types of 4h-pyrido[1,2-a]pyrimidin-4-one derivatives was investigated. Short synthesis of the investigated compounds was depicted. The gastroprotective effect was determined against acidified ethanol induced mucosal lesions in rats. The most effective compounds belong to unsaturated 4-oxo-4h-pyrido[1,2-a]pyrimidine-3-carboxamide derivatives, and the most active one contains a methyl group in position 6 and a cyclopentyl group on the nitrogen of the carboxamide group. Further pharmacological, biochemical and clinical studies may justify, that the representative of this type of compounds may be useful as prophylactic agents against gastric damage caused by non-steroidal antiinflammatory agents.
 
Article
Freshwater carps (Cyprinus carpio) were injected daily intraperitoneally either with vehicle (0.1 ml 95% ethanol/100 gm body wt), or 1,25(OH)2D3 (5 IU/100 gm body wt) and maintained either in artificial-freshwater, calcium-rich freshwater or calcium-deficient freshwater for 15 days. The specimens were sacrificed on day 1, 3, 5, 10 and 15 after initiation of the experiment and serum calcium levels were analysed. (i) Artificial freshwater: Serum calcium level of 1,25(OH)2D3 treated specimens increases progressively from day 3 to day 5. Thereafter, on day 10 and day 15 the level becomes normocalcemic. (ii) Calcium-rich freshwater: In vehicle-injected fish the serum calcium level increases progressively from day 3 to day 10. On day 15 the level becomes normocalcemic. In 1,25(OH)2D3-treated animals the serum calcium levels increase significantly from day 3 to day 5. The serum calcium level exhibits a slight fall on day 10 and day 15 although the value is still hypercalcemic. (iii) Calcium-deficient freshwater: In vehicle-injected specimens the serum calcium level shows a progressive hypocalcemia from day 3 to day 5. Thereafter the level increases thus resulting in hypercalcemia on day 15. In the 1,25(OH)2D3 treated specimens there is a significant increase in the serum calcium level from day 3 to day 10. On day 15 the level depicts a slight decrease.
 
Article
The novel 5-HT1A receptor antagonist WAY 100635 [(N-(2-(-4(2-metoxyphenyl)-1-piperazinyl)ethyl)-N-(2-pyridinyl)cyc lohexane carboxamide)] has been tested on 5-HT1A receptor-mediated inhibition of firing and intracellularly recorded hyperpolarisation of serotoninergic cells of the dorsal raphe nucleus (DRN) and on hyperpolarisation of hippocampal CA1 pyramidal cells. WAY 100635 selectively blocked 5-HT1A receptor-mediated responses of 5-HT, 8-OH-DPAT, lesopitron and 5-CT. The antagonism of the hyperpolarisation elicited by 5-CT was competitive in the DRN and non competitive in CA1, probably because of the existence of a 5-HT1A receptor reserve in serotoninergic cells of DRN.
 
Article
The aim of the present longitudinal study of four years was to analyse differences in growth patterns, age-related changes in body fat and physical performance in schoolchildren taking part either in normal or in elevated level physical education at school.Nine data collection sessions were carried out between 2002 and 2006 in 18 schools. The sample consisted of 521 non-athletic volunteer boys (PE=116, contrast = 405).The inter-group differences between mean height, body weight, body mass index, relative body fat content, mean scores in 30 m dash, 400 m run, and standing long jump as well as the patterns of change with age were analysed in this comparison. Between-observation differences were tested by repeated measures ANOVA. In case of a significant F-test Tukey's post-hoc tests were used. Age dependence was also studied by linear regression analysis.The between-group differences in mean height were not significant, but the slope of height increase with age was significantly greater in the PE boys. The PE boys were significantly lighter through all the nine observations and the slope of age-related weight increase was statistically faster in the group of contrast subjects. Both the BMI means and percent body fat means were consistently and significantly greater in the contrast group and faster increases were found in the group of the less active boys. The mean physical performances of the PE boys were consistently and significantly better. Their slopes of increase were statistically different.
 
Article
Unlabelled: Intraperitoneal administration of 5 mg/kg zopiclone a cyclopyrolone acting on the central benzodiazepine receptors was found to produce significant reduction of total lipids, total cholesterol and triglyceride in rats randered hyperlipidemic by intraperitoneal injection of Triton W-1339. Blood glucose level was also reduced. Flumazenil (10 mg/kg) potentiated the hypoglicemic effect of zopiclone but had no additional effect on serum lipids. PK 11195 (25 mg/kg) antagonized the hypolipidemic effects of zopiclone. In conclusion: 1. The central benzodiazepine receptors are not involved in the hypolipidemic activity of zopiclone. 2. The peripheral type benzodiazepine receptors are partly responsible, for the hypolipidemic activity of this cyclopirrolone. 3. The changes of blood glucose level induced by these drugs does not seem to be related to benzodiazepine receptors.
 
Article
The composition of contractile and regulatory proteins was studied in rat muscles with different functions. The rats were exposed to weightlessness for 18.5 days during a space journey in biosatellite Cosmos-1129. Under the effect of weightlessness the myosin light chain composition changed, the quantity of myosin LC-3 subunits increased in the soleus and extensor digitorum longus (EDL) while it decreased in the triceps and brachialis muscles. The experiments showed changes in the subunit composition of the TN-TM complex, too. The results obtained are in favour of a possible adequate transformation of fibril phenotypes of some (antigravitational) muscles under the effect of spaceflight.
 
Article
Isometric tension of glycerinated fibrils of different skeletal muscles was studied in white rats carried in the biosatellite "Cosmos-1129" for 18.5 days. Expression and trends of the changes in contractile properties of muscle preparations depend on their functional specialization. The most sensitive reaction was displayed by the soleus muscle which consists predominantly of slow fibres.
 
Article
In isolated guinea pig perfused hearts ICI 118.551, a selective beta 2 adrenoceptor antagonist, induced transient ventricular extrasystoles. Following the termination of the perfusion, a very significant increase of both the ventricular fibrillation threshold and the refractory periods were measured. In guanethidine pretreated hearts, ICI 118.551 failed to induce premature beats. At the same time the fibrillation threshold and refractory periods exhibited a very significant decrease. The perfusion of equimolecular concentration of metoprolol, a beta-1-adrenoceptor antagonist, and (+) propranolol, a quinidine-like compound, induced, in most experimental settings, similar results as ICI 118.551. Thus, besides its beta-2-adrenoceptor antagonist properties, ICI 118.551 presented other pharmacological actions.
 
11 β HSD1 protein levels in the liver and adipose tissue of control and diabetic Goto-Kakizaki rats. 11 β HSD1 protein was detected by Western blot analysis in the microsomal fractions. Upper panel: densitometric analysis of the blots, relative densities are shown, control liver = 1, means ± S.D., n=4, **p<0.01. Lower panel: typical blots 
Article
11beta-hydroxysteroid dehydrogenase type 1 (11betaHSD1) is a NADPH dependent oxidoreductase of the endoplasmic reticulum lumen which converts cortisone to cortisol and plays a role in the pathogenesis of metabolic syndrome and type 2 diabetes. The aim of our study was to investigate the correlation between the expression/activity of 11betaHSDI and obesity. Liver and adipose tissue microsomes of an obese (Zucker) and a non-obese (Goto-Kakizaki) type 2 diabetes model rat strains were used. 11betaHSDI expression was detected at mRNA, protein and activity level. The activity of 11betaHSD1 was increased in the adipose tissue and decreased in the liver of the obese Zucker rat, while its mRNA levels were significantly different only in the adipose tissue. In diabetic Goto-Kakizaki rat both the expression and the activity of 11betaHSD1 were elevated in liver, but not in adipose tissue. These results suggest that the prereceptorial glucocorticoid activation is different in the liver and adipose tissue of the two diabetes models. This phenomenon might be responsible for the obese and lean phenotypes in type 2 diabetes.
 
Article
According earlier, investigations nitrogen bridgehead compounds make a representative group of non-prostaglandin type gastroprotective agents. One member of this group is CHINOIN-127 (1,6-dimethyl-4-oxo-1, 6, 7, 8, 9, 9a-hexahydro-4H-pyrido-(1, 2a)-pyrimidine-3-carbox-amide). CHINOIN-127 is a potent non-narcotic analgesic and antiinflammatory agent and has a remarkable protective effect on indomethacin induced ulcer (ED50 = 25 mg/kg p.o.) and on acidified ethanol induced ulcer (ED50 = 26 mg/kg p.o.). In this study we examined the mechanism of action of cytoprotective effect of this drug and we made a comparison between the cytoprotective effect of 20% ethanol and 25 mg/kg CHINOIN-127. In the gastric mucosa of control rats we observed a balance between TxA2 and PGI2 (PGI2/TxA2 = 3.8) and between the cytoprotective prostaglandins (PGI2 and PGE2) and ulcerogen eicosanoids (TxA2 and leukotrienes) (PGI2 + PGE2/TxA2 + LTs = 3.9). 100% ethanol treatment causes disintegration of this balance, shifting the synthesis towards the ulcerogen eicosanoids production. CHINOIN-127 and 20% ethanol pretreatment improves the deranged balance between cytoprotective prostaglandins and ulcerogen eicosanoids. Our results demonstrate that CHINOIN-127 and 20% ethanol have a similar mechanism of cytoprotective action on ethanol induced ulcer in rats.
 
Article
It has been demonstrated that the novel antihypertensive compounds GYKI-12743 showed a potassium channel opening effect as studied in rabbit ear arteries with 86Rb+ as K+ marker. GYKI-12743 produced a concentration dependent 86Rb+ efflux in the same concentration range as the well-known K(+)-channel openers, pinacidil and cromakalim.
 
Article
Using the pithed rat preparation it has been proven that GYKI-12743 exerted its alpha-adrenergic blocking action only at the postsynaptic vascular level in the cardiovascular system. This new molecule failed to antagonize the presynaptic alpha 2-adrenoceptors of the cardiac sympathetic nerve endings. Thereby it was possible to demonstrate the first vasoselective postsynaptic adrenoceptor antagonist which potentially might be interesting in the cardiovascular therapy.
 
Article
GLG-V-13, a novel 3,7-diheterabicyclo[3.3.1]nonane, was examined both in vivo and in vitro in order to characterize its electrophysiological, haemodynamic and inotropic properties. Left ventricular epicardial monophasic action potential (MAP), surface ECG and mean arterial blood pressure (MBP) were recorded in six pentobarbital-anaesthetized, artificially ventilated and thoracotomized guinea-pigs. When studied in an intravenous dose interval ranging between 0.5 micrograms/kg and 500 micrograms/kg, GLG-V-13 dose-dependently lengthened the MAP duration (p < 0.05 at doses above 5 micrograms/kg), the atrioventricular conduction time (p < 0.05 at doses above 1 microgram/kg) and the RR interval (p < 0.05 at doses above 25 micrograms/kg). At the highest dose (500 micrograms/kg) these variables were increased by 30%, 13% and 23%, respectively. Only minor effects were noted on intraventricular conduction time (QRS interval) and MBP. In rabbit atrial and papillary muscle preparations, GLG-V-13 (0.32 to 3.2 mg/l) did not exert negative inotropic action. In 10 intact anaesthetized mongrel dogs, left ventricular endocardial MAP at 90% repolarization (MAP90) was measured during atrial pacing before and after administration of GLG-V-13, 3 and 6 mg/kg i.v., respectively.
 
Article
Cardiovascular disease is a leading cause of death worldwide. Diabetes mellitus is a well-known and important risk factor for cardiovascular diseases. The occurrence of diabetic cardiomyopathy is independent of hypertension, coronary artery disease, or any other known cardiac diseases. There is growing evidence that excess generation of highly reactive free radicals, largely due to hyperglycemia, causes oxidative stress, which further exacerbates the development and progression of diabetes and its complications. Diabetic cardiomyopathy is characterized by morphologic and structural changes in the myocardium and coronary vasculature mediated by the activation of various signaling pathways. Myocardial apoptosis, hypertrophy and fibrosis are the most frequently proposed mechanisms to explain cardiac changes in diabetic cardiomyopathy. Mammalian 14-3-3 proteins are dimeric phosphoserine-binding proteins that participate in signal transduction and regulate several aspects of cellular biochemistry. 14-3-3 protein regulates diabetic cardiomyopathy via multiple signaling pathways. This review focuses on emerging evidence suggesting that 14-3-3 protein plays a key role in the pathogenesis of the cardiovascular complications of diabetes, which underlie the development and progression of diabetic cardiomyopathy.
 
Article
The Al, Ca and Mg content of 147 kinds of foods and beverages, representing a large proportion of the Hungarian diet, has been determined using replicate samples. Dietary intakes of these minerals by 67 kindergarten children and 139 schoolchildren have been assessed. The richest sources of Al were: parsley, celery, gherkins, barley-malt; of Ca: dairy products, celery, parsley, savoy; of Mg: dried beans and peas, parsley, dill, maize-flour, rice, gherkins, chocolate. Flavouring agents (e.g. salt, pepper, paprika, caraway-seed) had very high concentrations of all three minerals and poppy-seeds that of Ca and Mg. The presence of bone-dust or fragments elevated the Ca content of some meats and cooked dishes. The main source of dietary intake of all three minerals was food; as opposed to F, the contribution of water-borne Al, Ca and Mg was negligible. Based on average values, the daily intake of all three minerals was satisfactory in both age groups. Mg intake was marginally below the recommended limit for a few children, but no signs of Mg deficiency were seen.
 
Article
Tachyphylaxis to SP decreased the effect of M15 and Gal(1-14)-[Abu8]SCY-I on gastric smooth muscles, without effect on the action of Gal. These findings support our initial hypothesis: the action of M15 and Gal(1-14)-[Abu8]SCY-I on the smooth muscles may not only be due to their agonist activity at Gal receptors, but may result from a subsequent stimulation of receptors for SP and perhaps for other tachykinins as well, however, a possibility that Gal analogues release endogenous SP can not be excluded. Further studies involving a tachykinin antagonist (spantide) are in progress at the moment. [1].
 
Article
Castrol-oil induced diarrhea in rats was potently prevented by compounds SR 140333 and SR 48968, the first a tachykinin NK1- and the second a NK2-receptor antagonist. SR 48968 was more effective and also reduced fecal water content.
 
Article
The authors investigated whether lorglumide a specific CCK-receptor antagonist affects the pancreatic actions of caerulein in female newborn Wistar rats. Pancreatic secretory response (expressed as the decrease in specific trypsin activity in the pancreas) was studied in 11-day-old rats following acute administration of saline (control), caerulein (0.3, 1, or 3 micrograms/kg s.c.) either without or with lorglumide (10 mg/kg s.c.). Lorglumide was given 15 min before caerulein. In chronic studies rats were treated 3x/day for 10 days from the day of birth (Day 1) with caerulein and lorglumide as above. On Day 11 the rats were decapitated and exsanguinated, their pancreas removed and analyzed. Acute administration of caerulein induced a dose-dependent depletion of specific trypsin activity from the pancreas and this was antagonized by lorglumide. Chronic treatment with each dose of the peptide increased total pancreatic trypsin content. Besides, the 3 micrograms/kg dose caused to increase pancreatic protein, DNA, and amylase content and to increase plasma corticosterone level. Chronic administration of lorglumide did not influence normal pancreatic growth, while it strongly inhibited the increase in trypsin content evoked by caerulein. However, lorglumide, given alone or in combination with caerulein, induced a significant increase in pancreatic amylase content without affecting plasma corticosterone level.
 
Article
The individual effect of desferrioxamine-B (DFOA), Na3Ca-diethylene-triaminepentaacetic acid (DTPA), DL-penicillamine (PA) and Na-salicylate (SA) has been examined as well as the effect of mixed-ligand treatment on the retention and elimination of 144Ce in mice. It was found that 144Ce could easily be mobilized by a single dose of DTPA. Mixed-ligand (MLCs) treatment did not change the deposition characteristics and translocation kinetics of 144Ce.
 
Article
In animal experiments the effects of 7.5 Gy whole-body irradiation (LD50/30) and/or of radioprotecting compound (WR-2721) on the retention and elimination of 144Ce were investigated. It was stated that in the first three days there was an increase in the deposition of 144Ce after whole-body irradiation and upon treatment with radioprotective compound WR-2721.
 
Article
LB-145 is a macrocyclic ligand, which forms, 200 times more stable complex with Stroncium (Sr) ions, than with calcium ones. The product is not toxic, it has no effect on circulation, respiratory system. 85,90Sr and 144Ce were given oral, i.p., s.c. or by inhalation, LB-145 either prophylactic or 30 (60) minutes after the radiointoxication i.v. or i.p. to the animals. The isotope contents of the organism were measured by whole body autoradiography, liquid scintillation, or by NK 350 ratemeter. One injection given prophylactic inhibited the incorporation of isotopes into the organism, within 24 hours after radiointoxication 75-80% of the isotopes were excreted by urine and faeces on the first day, 90-95% excreted on the first week. Also the isotope contents of femur and scissors were mobilised. The suggested human dose-0.5 g/70 kg bw-can be life-saving antihavaric injection.
 
Article
The tripeptide aldehyde GYKI-14766 (D-MePhe-Pro-Arg-H) synthesized by Bajusz et al. in 1975 is a specific, reversible thrombin inhibitor. It was found effective in vitro in clotting time assays as well as in vivo in thrombosis models. To study the biochemical effects of the inhibitor various experimental setups were applied. First we measured the binding of thrombin to platelets using 125J-thrombin. KD was 55 nM. Second, 125J-thrombin was displaced by thrombin or by a GYKI-14766-thrombin-complex with similar efficacy. However, the binding of thrombin to the platelets increased the intracellular free Ca2+ concentration, but the inhibitor-thrombin complex did not influence it. Analyzing the kinetics of the reactions involved we found that the formation of the GYKI-14766-thrombin complex was slower than the triggering of the platelet Ca2+ signal by thrombin.
 
Article
The effect of hemorrhagic arterial hypotension on local cerebral glucose metabolism was studied on 33 rats. The mean arterial pressure was set with the aid of a reservoir at 80, 60, 50 and 40 mmHg pressures. Local cerebral glucose utilization was measured with the 14C-2-D-deoxyglucose accumulation autoradiographic technique. Local glucose consumption decreased somewhat in cortical structures when mean arterial pressure was reduced to 60-50 mmHg. Further decrease in mean arterial pressure to 50-40 mmHg caused inhomogeneity of tissue metabolism. Columns and patches of high glucose consumption interchanged with areas of very low glucose consumption in most telencephalic and cerebellar gray matter structures. Brain stem and white matter structures seem to be less sensitive to decreased mean arterial pressure in the range studied. We found a decrease in glucose utilization rather than an increase with decreasing mean arterial pressure down to 60-50 mmHg (in the range of the autoregulation of cerebral circulation). This finding makes it improbable that autoregulation would be connected with elevated anaerobic metabolism of the tissue. Patchy areas and columns of high glucose consumption found at 50-40 mmHg in all probability reflect areas of increased anaerobic metabolism of glucose. Here, circulation was not enough to transport adequate quantity of oxygen to the tissue, but still it transported relative large amount of glucose. Columns and patches of very low glucose consumption should reflect areas, where circulation was inadequate to transport both enough glucose and oxygen.
 
Article
In CFY rats pseudopregnancy (PSP) was induced by mechanical stimulation of cervix uteri. On the days 1 or 7 of PSP indvelling catheter was built in one of the jugular veins and blood was collected daily until 7th or 14th days of PSP respectively, meanwhile the animals were daily injected with clenbuterol (0.1 mg/kg bw), fenoterol (0.5 mg/kg bw), ritodrin (1.0 mg/kg bw), propranolol (2.0 mg/kg bw) or 1.0 ml/kg bw 0.9% NaCl subcutaneously. From the blood samples progesterone (P) and oestradiol-17 beta (E2) were determined by RIA. beta 2-adrenergic agonists did not influence the serum levels of P either in the first or in the second half of PSP and the propranolol failed to alter also the serum levels of P during the PSP. Clenbuterol and ritodrin, however, decreased the serum levels of E2 in the first half of PSP, while in the second half of PSP fenoterol and ritodrin elevated, the propranolol diminished it. It was supposed that in PSP rats beta 2-adrenergic mechanism has a more pronounced effects on the theca-interstitial cells than that of the luteal cells.
 
Article
Sixty-one daily profiles of blood-spot 17-hydroxyprogesterone derived from patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency were analysed to determine the age of appearance of circadian rhythm in hypothalamo-pituitary-adrenal activity. The results revealed that typical circadian adrenocortical rhythm is established at approximately three months after birth. In conclusion, the maturation of supra-hypothalamic brain structure proceeds normally also in humans with constant low level of cortisol in blood.
 
Article
In 15 cynomolgus monkeys between days 30-160 of gestation, tissue levels of oestrone (E1), oestradiol 17 beta (E2) and progesterone (P4) were assayed by RIA in the myometrium and the placenta. Myometrial samples were subdivided as follows: inner and outer layers adjacent to the placental area (IMP and OMP) and inner and outer layers from antiplacental areas (IMAP and OMAP). Steroid levels (ng/g wet wt) were in the range of known plasma values (ng/ml) and there was no asymmetric distribution of steroids between the various locations. When the results obtained in all the layers were pooled the gestational profiles indicated a decrease of E1 between days 80-130, whereas at the same time E2 and P4 increased. The ratio P4/E2 was 8 on day 40, 17 on day 80 and 9 on day 160. In the placenta, levels of E2 and P4 were 4 times higher, levels of E1 10 times higher than in the myometrium. Gestational profiles of the three steroids in the placenta increased from day 30 to day 160. Myometrium steroid content therefore does not appear to be a simple reflection of steroid diffusion from the site of production.
 
Article
Testicular delta 5-3 beta- and 17 beta-hydroxysteroid dehydrogenase (delta 5-3 beta- and 17 beta-HSD) activities of rat are inhibited in vitro by a wide range of lithium concentration. The inhibitory effects of lithium are evident at a concentration of 2.5 mM which is easily achieved during the treatment of acute manic patients with lithium. This suggests that lithium exerts a direct inhibitory effect on testicular hydroxysteroid dehydrogenase activities.
 
Article
Intestinal mucosal damage was produced in rats by the s.c. administration of indomethacin (10 mg/kg). The number and severity of the small intestinal mucosal lesions was recorded. Different doses of prostacyclin (PGI2), 7-oxo-PGI2 and 17-aza-PGF2 alpha (0.25-0.5-1.00 mg/kg) were given i.p. at the time of administration of indomethacin. The effects of these compounds were studied on the number and severity of the small intestinal mucosal lesions. It was shown that (1) all tested compounds inhibited the number and severity of the intestinal mucosal lesions, however, to different extent; (2) the inhibition of the development of small intestinal mucosal damage displayed a dose-response relationship; (3) 17-aza-PGF2 alpha was found to have the most potent effect on the development of the intestinal lesions as well as on the development of gastric mucosal damage produced by ethanol.
 
Article
According to standard textbooks, the last episode of European New Age plague pandemic died out by 1720 in Marseilles. Despite this allegation, the pandemic continued in well-documented new outbreaks, which attacked and devastated Central and Eastern Europe throughout the first half of the 18th century. At the beginning, military campaigns spread the infection out of the Ottoman Empire. Later on commercial goods took over this role via land or sea from Asia or out of the eastern Mediterranean region. Finally, the plague in Europe--except Russia and the Ottoman Empire--"died out" virtually by the end of the 18th century. Explaining this, there many scientific reasons were suggested: 1. Oriental rat fleas as main vectors of infection could not tolerate any more the European weather conditions (although there were no virtual climate changes in the last 300 years). 2. Black rats that lived in close proximity to man, were being outplayed by brown rats living rather outside of human habitats; 3. There emerged less virulent Yersinia strains that caused natural human immunisation. In spite of these suggestions, which may have contributed to the success, joint civil and military health authorities blocked the plague indeed, as a result of disciplined and relentless law enforcement. In Hungary, respectively in the Hapsburg Empire, well-advised health legislation backed up the effectiveness of local authorities. Following the last great devastation in 1738-1740, the General Norm of Health Service--a voluminous decree--summed up by 1770 all the time honoured empiric rules of foregoing centuries. It can be excellently demonstrated, how exactly the empiric rules discovered a century later met scientific facts of physiology and microbiology.
 
Article
Effects of different doses of 17 beta-estradiol (1, 2 and 4 micrograms/g, 3 consecutive days injections) on the protein, RNA and DNA contents of cerebrum (CB), cerebellum (CE), midbrain (MB), medulla oblongata (MO) and spinal cord (SC) of female non-vitellogenic (NV) and vitellogenic (V) Singi fish (Heteropneustes fossilis Bloch) were investigated. The amounts of these macromolecules in all these substructures of the central nervous system were enhanced on the 4th and/or 7th day in NV fish by estradiol depending on the dose. The higher dose(s) caused more marked effect. The dose of 1 microgram/g was ineffective in case of protein and mostly in case of DNA. There was no enhancement of protein content with any dose of estradiol on the 4th day in CE, MB, MO and SC, but in CB 4 micrograms of estradiol/g increased the protein content on this day. However, the increase was marked on the 7th day in all substructures. The enhancement of RNA content was elicited earlier (4th day) even with lower dose of 1 microgram/g in NV fish in most of the substructures, except MO. With exception of this substructure again, the DNA content of any part did not increase with the hormone on the 4th day with 1 microgram of estrogen/g. The changes in protein and nucleic acid contents of the different substructures of central nervous system in V fish with 17 beta-estradiol were mostly opposite to those in NV fish. Depending on the dose and time, protein and RNA contents of these parts decreased with estradiol in V fish. No change in DNA content, however, was found, except MO where this cellular constituent was surprisingly enhanced on the 4th and 7th day with all doses of estradiol used. The spinal cord of V fish did not show any change in RNA and DNA contents with the hormone. Thus a reproductive stage-specificity of estrogen action in fish brain is documented.
 
Article
On the day of dioestrus II rats were given 5, 10 or 15 mg/kg of cadmium chloride (CdCl2), or 1, 0 ml/kg of 0.9% NaCl solution. Then ovarian cycle was checked daily for a period of 12 cycle length. On the day of oestrus or expected oestrus in the 13th cycle the animals were anaesthetized with pentobarbital and cannulas were inserted in one of the femoral arteries and veins and in one of the utero-ovarian veins. Five-minute blood fractions were collected for 40 minutes and following the first blood samples 10 IU of hCG were injected iv. Ovarian venous outflow and blood pressure were continuously recorded. From the blood fractions progesterone (P) and oestradiol-17 beta (E2) were determined with RIA and the P and E2 secretion rates of ovary were calculated. Ovaries were excised and oviducts were flushed for counting oocytes. CdCl2 shortly after its administration induced a (dose-dependent) anoestrous period which turned into regular or irregular cycles depending on the dose. Part (28-32%) of the oestrous animals (14% that of the controls) remained unovulatory, when ovulation occurred normal number of ova was found. None of the doses of CdCl2 has influenced the blood pressure of animals and blood flow of the ovary. The basal secretion rate of P and E2 was not changed in the ovary compared to the controls. The hCG induced rise of P secretion, however, in the animals treated with 5 and 10 mg/kg bw CdCl2 was diminished and delayed, while in the animals treated with the 15 mg/kg Cd dose a complete lack of response was observed.
 
Article
The aim of this study was to explore effects on anxiety-like behavior of the D2 dopamine receptor agonist, quinpirole and of the D2 dopamine receptor antagonist, sulpiride given alone or in combination with a low dose of 17β-estradiol (17β-E2) to ovariectomized (OVX) rats. Two weeks after surgery, OVX rats began 14 days of treatment with the vehicle, a low dose of 17β-E2 (5.0 μg/rat, s.c.), quinpirole (0.1 mg/kg, i.p.), sulpiride (10.0 mg/kg, i.p.), quinpirole plus 17β-E2 or sulpiride plus 17β-E2. The animals were then tested in the black and white model (BWM) and the open field test (OFT). Quinpirole (0.1 mg/kg, i.p.) administered alone or in a combination with a low dose of 17β-E2 (5.0 μg/rat, s.c.) resulted in anxiolytic-like effect in OVX rats in the BWM. Repeated treatment of quinpirole and 17β-E2 profoundly increased anxiolytic-like effect of the single substances they exert per se. Co-administration of quinpirole with 17β-E2 increased frequency of rearing and grooming in OVX rats in the OFT. Sulpiride (10.0 mg/kg, i.p.) treatment failed to alter anxiety-like behavior in OVX rats in the BWM. In addition, sulpiride blocked the anxiolytic-like effect of 17β-E2 in OVX rats. Application of neither sulpiride nor sulpiride plus 17β-E2 led to any changes of rearing and grooming behavior in OVX rats in the OFT. The results of the present study suggest that 17β-E2 and quinpirole interact to exert anxiolytic-like action and that each of these drugs can potentiate effects of each other. Further research is needed to elucidate detailed mechanisms by which quinpirole and 17β-E2 exert synergistic effect on anxiety-related behavior.
 
Article
We investigated the effects of 17beta-estradiol (E 2 ) and vitamin E on lipid peroxidation and antioxidant levels in brain cortex of diabetic ovariectomized (OVX) rats. Forty-two rats were equally divided into seven groups: Control; OVX; OVX+E 2 ; OVX+E 2 +vitamin E; OVX+diabetic; OVX+diabetic+E 2 and OVX+diabetic+E 2 +vitamin E. Then, E 2 (40 microg kg -1 /day) and vitamin E (100 mg kg -1 /day) were given. Glutathione peroxidase (GSH-Px), catalase (CAT), superoxide dismutase (SOD), glutathione (GSH), vitamin A and beta-carotene in brain were decreased (p<0.05) when compared with control in OVX but MDA in brain and glucose in plasma were elevated (p<0.05). The antioxidant levels in brain (p<0.05) increased although MDA (p<0.05) in brain and glucose (p<0.05, p<0.01) in plasma decreased in OVX after E 2 and E 2 +vitamin E supplementation. The activities of GSH-Px (p<0.001, p<0.01), CAT (p<005, p<0.001) and SOD (p<0.001) and the levels of GSH (p<0.001), vitamin A (p<0.05) and beta-carotene (p<0.001, p<0.05) were lower in the brain of OVX diabetic rats, while MDA in the brain and glucose in the plasma were higher (p<0.001). The antioxidant enzymes (p<0.05, p<0.01), GSH, vitamin A and beta-carotene (p<0.01, p<0.001) in brain increased while MDA in brain and glucose in plasma decreased (p<0.01, p<0.001) in diabetic OVX after treatments. Finally, the E 2 and E 2 +vitamin E supplementation to diabetic OVX and OVX rats may strengthen the antioxidant system by reducing lipid peroxidation.
 
Article
Although much is known about the protective effect of acute estrogen therapy in cerebral ischemia, relatively little is known about the importance of apoptosis and cerebral plasticity in this mechanism. In this work 10 min global cerebral ischemia was produced by transient bilateral carotid occlusion in 4-month-old ovariectomized female gerbils. In every of our experimental group (sham for ischemia group, ischemia group and ischemia + a high, single dose 17β-estradiol pre-treatment group) apoptotic (bcl-Xl, bax) and cerebral plasticity (GAP-43, synapsin-I, nestin) hippocampal genes' expression was measured four days after surgery. Expression of the anti-apoptotic bcl-Xl (p<0.01) and the cerebral plasticity marker synapsin-I and nestin (p<0.01) increased with acute estrogen pretreatment in ischemic animals. No change, however, in bax or GAP-43 expression was detected in estrogen treated animals compared to ischemic gerbils. These results suggest that acute estrogen therapy has anti-apoptotic effect and increases cerebral plasticity, which play an important role in cytoprotection or cerebroprotection.
 
Article
Functions of the antioxidative system and cytokines are important factors that can influence the development of cancer. The aim of this study was to determine gender-related differences in the concentration of inflammatory cytokine IL-18 and alterations of antioxidative system parameters after surgical treatment of renal cell carcinoma patients. The study comprised 40 patients (22 women and 18 men). The level of peroxidation product malonodialdehyde (MDA), the status of the antioxidative system and the concentration of interleukin-18 (IL-18) were analyzed. A significant difference in the changes of antioxidative system reflecting parameters was observed according to the gender. In the male group with higher IL-18 concentration after surgery the level of MDA was lower, while in the women group it did not change and the level of catalase activity was higher; superoxide dismutase activity was higher in both groups. It is important to notice that our previous study (where the data were not analyzed in respect of gender) showed that the level of IL-18 was significantly higher after surgical treatment if MDA content was increased. More detailed studies are required to confirm in which cases association between IL-18 concentration and MDA level is related to cancer progression and in which cases - to the better prognosis depending on the patients' gender.
 
Article
Ervin Bauer is one of the first theoretical biologists distancing his ideas both from vitalism and mechanicism. He formulated the principle of permanent non-equilibrium of living systems (Bauer's principle) in terms of thermodynamics in 1920. Bauer's scientific path can be divided into three periods. In the early 1920s he proposed his principle as an axiom that cannot be derived from contemporary natural sciences. In the late 1920s he reformulated it in a way that it could be subjected to experimental testing. Summarizing his views in the 1930s in his book, Theoretical Biology, he tried to show that his axiom is indeed the fundamental principle of biology. This later view was anachronistic in spite of many striking insights of Bauer. The energetic formulation of Bauer's principle is, however, a realistic characterization of living organisms and it can be derived from the theory of open systems - in fact it contributed to the formulation of that theory. Bauer's principle can be incorporated into non-linear thermodynamics of irreversible processes.
 
Article
Swiss mice were treated intraperitoneally with AET, 5-HT, MEA, or GSH, in a dose of 80 mg/kg of body weight, on the first day of gestation. On the 19th day of pregnancy, the fresh weight of liver of the foetuses, as well as glycogen content in 1 g of fresh tissue and in the whole organ were analysed. The determination of glycogen content in the foetal liver were made according to the anthrone method. As compared with controls, in the remaining groups of mice a lower fresh weight of foetal liver less glycogen per g of fresh tissue and a smaller total amount of glycogen in the whole organ were found. Among the compounds, AET appeared to be more toxic than 5-HT, MEA, and GSH.
 
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György Csaba
  • Semmelweis University
Gábor Pavlik
  • University of Physical Education
Ilona Szollosi Varga
  • University of Szeged
Márta Kotormán
  • University of Szeged
Do Hai
  • the northern national brood center for marine culture