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ABSTRACT: 3,4-Methylenedioximethamphetamine (MDMA, ecstasy) is a worldwide abused stimulant drug, with persistent neurotoxic effects and high prevalence among adolescents. The massive release of 5-HT from pre-synaptic storage vesicles induced by MDMA followed by monoamine oxidase B (MAO-B) metabolism, significantly increases oxidative stress at the mitochondrial level. l-Carnitine and its ester, acetyl-l-carnitine (ALC), facilitate the transport of long chain free fatty acids across the mitochondrial membrane enhancing neuronal anti-oxidative defense. Here, we show the potential of ALC against the neurotoxic effects of MDMA exposure. Adolescent male Wistar rats were assigned to four groups: control saline solution, isovolumetric to the MDMA solution, administered i.p.; MDMA (4x10 mg/kg MDMA, i.p.); ALC/MDMA (100 mg/kg 30 min of ALC prior to MDMA, i.p.) and ALC (100 mg/kg, i.p.). Rats were killed 2 weeks after exposure and brains were analyzed for lipid peroxidation, carbonyl formation, mitochondrial DNA (mtDNA) deletion and altered expression of the DNA-encoded subunits of the mitochondrial complexes I (NADH dehydrogenase, NDII) and IV (cytochrome c oxidase, COXI) from the respiratory chain. Levels of 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) were also assessed. The present work is the first to successfully demonstrate that pretreatment with ALC exerts effective neuroprotection against the MDMA-induced neurotoxicity at the mitochondrial level, reducing carbonyl formation, decreasing mtDNA deletion, improving the expression of the respiratory chain components and preventing the decrease of 5-HT levels in several regions of the rat brain. These results indicate potential benefits of ALC application in the prevention and treatment of neurodegenerative disorders.
Neuroscience 11/2008; 158(2):514-23. · 3.38 Impact Factor
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ABSTRACT: Methamphetamine (Meth) neurotoxicity upon the mesencephalic dopaminergic systems was demonstrated in the adult, both in humans and in experimental models. In the rat, the development and maturation of the dopaminergic systems is accomplished during the first month of postnatal life, a period of particular vulnerability to environmental influences. In this study, the effect of Meth exposure during the first month of life was assessed in the nigrostriatal dopaminergic system of the rat. For this purpose, Wistar rat litters were culled to 8 pups, retaining preferentially 4 males and 4 females, which, in the day following birth (postnatal day 1, PND1), were randomly attributed to either the Meth or control group. Meth-groups were administered 10 mg of (+)-methamphetamine hydrochloride/kg body weight/day, subcutaneously, twice daily, from PND1 until PND29; control groups received isovolumetric doses of saline. Animals were sacrificed at PND30. Males exposed to Meth during the first month of life had increased tyrosine hydroxylase (TH) activity both in the caudate-putamen and substantia nigra. Males also had increased nigral TH mRNA levels, as assessed by in situ hybridization. These effects did not exist in females. These results support the evidence that Meth exposure during the first month of life in the rat has a gender-specific stimulatory effect upon the maturation of TH, the key enzyme for dopamine biosynthesis in the nigrostriatal dopaminergic system.
Annals of the New York Academy of Sciences 10/2000; 914:431-8. · 3.15 Impact Factor
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ABSTRACT: The visual system of rodents is affected if exposure to drugs, e.g., cocaine, occurs during prenatal or early postnatal development. This study aims to evaluate, in an experimental model of neonatal exposure to cocaine in the rat, the immunocytochemical expression of tyrosine hydroxylase in the retina and the levels of different neurotransmitters and its metabolites. Male Wistar rats were given 15 mg cocaine hydrochloride/kg body weight/day, subcutaneously, in two daily doses, from the day after birth (PND1) to PND6, 13, and 29. Controls were given 0.9% saline. Groups of rats were perfused at PND7, 14, and 30 with fixative, and the retinas were processed as wholemounts, and immunostained with the antibody anti-TH. Other groups were decapitated, and the retinas were dissected and processed by high performance liquid chromatography with electrochemical detection (HPLC-EC) for determination of dopamine and metabolites (DOPAC and HVA). A reduction in the retinal surface area was detected in the PND30 cocaine group, and a decrease in the density of the small TH-IR cells was found in the PND14 cocaine group although not reaching significant levels. The other quantitative parameters did not differ between the control and cocaine groups. The levels of neurotransmitters did not significantly differ between the groups at any age. These results show a differential vulnerability of the dopaminergic system of rats exposed neonatally to cocaine when compared with the effects found after prenatal exposure to the same drug.
Annals of the New York Academy of Sciences 10/2000; 914:418-30. · 3.15 Impact Factor
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ABSTRACT: In the last curricular review (1995/96) radiological anatomy was introduced as an innovation in the program of the course of clinical anatomy of the Medical School. Since computer-based media are known to facilitate the understanding of the human body, computer technology was selected in the academic year of 1997/98 as an elective educational tool to teach radiological anatomy. CD-ROMs were introduced as additional instructional resources in 1997/98. This technology aimed to provide educational support to the program, namely, to the sessions of radiological anatomy in each section of the course: head, neck, thorax, abdomen, pelvis and perineum. A questionnaire was designed to evaluate the opinion of the students enrolled in this course, focusing on the teaching sessions of radiological anatomy. Of 152 students, 135 (88.8%) returned the questionnaire. To describe the relationship between the value of this technology and several aspects of its organisation and adequacy, the Spearman rank correlation coefficient was used; canonical correlation was used for the various practical sessions. The comments of students were very positive emphasising the quality of the media, organisation of the course, immediate feedback, degree of interactivity and simplicity of use; they suggested a larger facility for the computers and acquisition of more programs and hardware. The positive evaluation of the use of the CD-ROMs in clinical anatomy allows us to foresee the formal integration of these instructional tools in the whole course, and not to restrict its use to specific units within the course.
Surgical and Radiologic Anatomy 02/2000; 22(1):29-34. · 1.06 Impact Factor
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ABSTRACT: Handouts were developed to support the program of Clinical Anatomy in the Medical School of Porto, and since 1996/97 alterations have been made to improve their format and content with our educational objectives in mind. A questionnaire was designed to evaluate the opinion of second-year medical students enrolled in the program. Students were asked about their approval of the way handouts were organized and their usefulness, especially for lectures and practical sessions on physical examination, sectional and imaging anatomy, anatomical variations and malformations and case studies. Of 152 students, 138 (90.8%) returned the questionnaire. To describe the relationship between the value of handouts and several aspects of their organization and adequacy, the Spearman rank correlation coefficient was used for lectures, and canonical correlation for the various practical sessions. Students fully approved the way the handouts of lectures and practical sessions were organized (81.8% and 87%, respectively), their presentation (74.6% and 86.2%), relevance (88.3% and 85.5%), usefulness in understanding the lectures (77.6%) and their value in preparing for practical sessions (83.3%). Handouts were considered highly useful for case studies (90%), physical examination (81.9%) and sectional anatomy (65.7%). Students stating a higher degree of utility of the handouts emphasized that they were useful-indeed essential-in preparing for sessions, and noted their objectivity. The evaluation of the handouts was highly favorable and showed that they can be used as a guide through the complexities of an innovative program of Clinical Anatomy.
Clinical Anatomy 02/1999; 12(5):337-44. · 1.29 Impact Factor
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ABSTRACT: Taking into account that methamphetamine (MA) is a popular recreational drug among young adult women, i.e., in gestational age, the present model aims to assess the effects of its exposure during development. In this experimental model, MA effects are assessed in the rat during the first month of life, regarding both general growth parameters, and gross morphological effects in the retina as part of the evaluation of sensory systems. Experimental animals were obtained from 60-day-old nulliparous females. Litters were culled to 8 pups (4 males and 4 females, whenever possible), individually marked and weighed every two days. Experimental groups received 10 mg (+)methamphetamine hydrochloride kg body weight/day, subcutaneously, twice daily, from postnatal day (PND) 1 to the day before sacrifice; control groups received isovolumetric doses of saline, in the same protocol. Pups were weaned on PND 21. Groups were sacrificed on PND 5, 7 and 30. Animals exposed to MA presented increased percentage of retinal hemorrhages (18, 7 and 11% on PND 5, 7 and 30, respectively) compound to control groups (2% on PND 7, 0% on PND 5 and 30). On PND 30, the mean body weight of males exposed to MA was 75% of the mean weight of male controls, whereas for females, mean body weights were 70% of those of female controls. These findings support the view that developmental parameters in the rat are deleteriously affected by early exposure to MA.
Annals of the New York Academy of Sciences 06/1998; 844:310-3. · 3.15 Impact Factor
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ABSTRACT: Taking into account that methamphetamine (MA) is a popular recreational drug among young adult women, i.e., in gestational age, the present model aims to assess the effects of its exposure during development. In this experimental model, MA effects are assessed in the rat during the first month of life, regarding both general growth parameters, and gross morphological effects in the retina as part of the evaluation of sensory systems. Experimental animals were obtained from 60-day-old nulliparous females. Litters were culled to 8 pups (4 males and 4 females, whenever possible), individually marked and weighed every two days. Experimental groups received 10 mg (+)methamphetamine hydrochloride kg body weight/day, subcutaneously, twice daily, from postnatal day (PND) 1 to the day before sacrifice; control groups received isovolumetric doses of saline, in the same protocol. Pups were weaned on PND 21. Groups were sacrificed on PND 5, 7 and 30. Animals exposed to MA presented increased percentage of retinal hemorrhages (18, 7 and 11% on PND 5, 7 and 30, respectively) compared to control groups (2% on PND 7, 0% on PND 5 and 30). On PND 30, the mean body weight of males exposed to MA was 75% of the mean weight of male controls, whereas for females, mean body weights were 70% of those of female controls. These findings support the view that developmental parameters in the rat are deleteriously affected by early exposure to MA.
Annals of the New York Academy of Sciences 04/1998; 844(1):310 - 313. · 3.15 Impact Factor
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ABSTRACT: The purpose of this study was to investigate the differential effects of prenatal exposure to psychostimulants, e.g., cocaine or amphetamine, on basic growth parameters and morphometry of the medial prefrontal cortex of the rat. A group of pregnant Wistar rats was given 60 mg/kg body weight/day of cocaine hydrochloride and another group 10 mg/kg body weight/day of d-amphetamine sulfate, subcutaneously, from gestational days 8 to 22. Control groups of pregnant rats were pair-fed; litters were culled to eight pups (4 males and 4 females) weighed every other day until postnatal day 30 and every week until day 90. The body weight growth patterns modelled by a Gompertz curve were different in rats prenatally exposed to the two psychostimulants. Rats exposed to amphetamine had on average a slower growth than those exposed to cocaine, reaching an identical estimated adult weight. Allometric relationships between forebrain and body weight and cerebellum and body weight were described by two distinct postnatal growth phases that are different among the experimental groups. In the comparison of the two psychostimulants the relative cerebellum/body growth is lower in the offspring of the cocaine group than in the amphetamine group between PND14-PND30; between PND30-PND90 the relative growth rate is considerably higher in the offspring of the cocaine dams compared to that of the amphetamine dams. Groups of perfused animals were selected at postnatal days 14 and 30 to analyze the morphometric organization of the medial prefrontal cortex. In serial celloidin sections the volumes of the prefrontal cortex were determined; the number of neurons per unit volume of reference area was calculated using the stereological technique of the disector. The changes found in the morphometric parameters show a catch-up at postnatal day 30 of the "increased" density of neurons of the medial prefrontal cortex found at postnatal day 14. These data show differential growth patterns of offspring from cocaine- and amphetamine-exposed rats; a delayed development in the achievement of normal morphometric parameters of neurons in the prelimbic subarea of the medial prefrontal cortex occurs in the prenatally amphetamine-exposed offspring at early ages, and a catch-up is found after the first month of life. Complementary studies are needed to assess whether these changes have functional implications in the rats exposed prenatally to psychostimulants.
Annals of the New York Academy of Sciences 11/1996; 801:256-73. · 3.15 Impact Factor
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ABSTRACT: Clinical and basic research in the area of drugs of abuse are of utmost importance since they provide the necessary background for health programs in one of the main problems of contemporary society. The available data in this field demonstrate that acute, subacute and/or chronic abuse of illicit drugs, e.g., cocaine, alters the neurochemistry and functioning of the neural circuitries. Although recent works demonstrated that the visual system is lesioned after exposure to cocaine during the active periods of development, no studies have provided detailed information on the effects of these substances on the development of this sensory system. The present paper will report: 1) the vulnerability of the developing visual system to gestational exposure to cocaine; 2) the effects of cocaine in the visual system during the more active periods of development in humans and, as far as possible, the establishment of homologies with animal models where exposure is made in corresponding periods of human gestation, and 3) the characterization of the vascular disruption caused by ischemic/hypoxic mechanisms. The clinical study focused the ophthalmologic evaluation of newborns exposed in utero to illicit drugs. Newborns exposed to cocaine in utero showed marked vascular disruption in the retina: superficial and deep hemorrhages that, although morphologically similar to neonatal retinal hemorrhages, presented a longer reabsorption time when compared with the neonatal hemorrhagic lesions due to birth trauma in the general population. Prolonged eyelid edema was also a prominent finding. The animal study was conducted in Wistar rats exposed prenatally (gestational days 8 to 22) and postnatally (postnatal days 1-6, 1-13 and 1-29) to 60 mg/kg body weight/day and 15 mg/kg body weight/day, respectively, to cocaine hydrochloride administered subcutaneously; control groups included pair-feeding during the same experimental periods. Similar alterations to those observed in the newborns where exposure to cocaine was affirmative, were found: intraretinal hemorrhages allied to signs of chronic ischemia both in the outer retina-photoreceptor rosettes and in the inner retina-epiretinal glial membranes. Taking into consideration that the visual system is one of the more important sensory systems, the identification and characterization of these alterations, the similarity between animal and human findings, and their relation with cocaine per se, can provide a sound data base for illicit drug prevention programs.
Annals of the New York Academy of Sciences 11/1996; 801:274-88. · 3.15 Impact Factor
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ABSTRACT: This study was designed to investigate the effects of prenatal exposure to amphetamine in the organization of the medial prefrontal cortex of the rat, by an evaluation of growth, morphometric and neurochemical parameters. Pregnant Wistar rats were given 10 mg/kg body weight/day of D-amphetamine sulfate, subcutaneously, from gestational days 8 to 22. Control groups of pregnant rats were injected with saline, pair-fed or non-manipulated; litters were culled to eight pups (four males and four females), weighed every other day until postnatal day 30 and every week until day 90. The Gompertz model was used to study body weight evolution and the estimated growth parameters were not significantly different in the experimental groups. At postnatal days 14 and 30, the volumes of the prefrontal cortex, the fraction of neuropile occupied by neurons and the number of neurons per unit surface are were determined. The number of neurons per unit volume of reference area was calculated using the stereological technique of the dissector. For neurochemical analysis, the medial prefrontal cortex was dissected to measure the concentration of dopamine, serotonin and their metabolites. The allometric relationship of forebrain/body growth pointed to a mechanism of sparing and compensatory growth in the amphetamine exposed group. The changes found in the number of neurons per unit volume at postnatal day 14 show a catch-up at postnatal day 30. A decrease in serotonin levels was found in the amphetamine group compared with the pair-fed control, which was reflected in the ratio of serotonin to its metabolite, 5-hydroxyindolacetic acid. These changes, whether permanent or transitory, raise the possibility that some of the effects of prenatal exposure to amphetamine may be due to modifications in the neurotransmitter levels of serotonin.
International Journal of Developmental Neuroscience 09/1996; 14(5):585-96. · 2.42 Impact Factor
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ABSTRACT: There is a growing consensus that the development of the eye is affected by prenatal exposure to cocaine. Considering that the retina is affected by prenatal cocaine exposure, that this drug affects the dopaminergic systems, that the dopaminergic cells in the retina show a well-defined pattern of development and that they can be specifically stained in wholemounts by the antibody anti-tyrosine hydroxylase (TH), this study was undertaken to evaluate the effects of in utero cocaine exposure on the dopaminergic cells of the rat retina. Pregnant Wistar rats were given 60 mg (kg body weight)-1 day-1 of cocaine hydrochloride, subcutaneously, from gestational days 8 to 22. Control groups of pregnant rats were pair-fed. At PND14, 30 and 90, male offspring from different litters were perfused with fixative and the retinas processed as wholemounts and immunostained with the antibody anti-TH. Rats from other groups were decapitated at the same post-natal ages, the retinas dissected and processed by neurochemical techniques to measure the concentrations of dopamine, its metabolites and the turnover of dopamine. There was a significant increase of the retina surface area between PND14-30 in the control group, which was not found in the cocaine group. The density of the immunostained small TH cells was lower in the cocaine groups. No drug-effects were detected in the density of the large TH cells. The densities of the total large and small cells in the superior, inferior and nasal hemiretinas were similar to those found in the whole retinas; however, in the temporal hemiretinas of the cocaine groups, the density of the large TH cells was higher and of the small TH cells was lower than in controls, resulting in an absence of effects on the total density of TH-cells in this hemiretina. A transient increase in the level of dopamine metabolite (DOPAC) and of the turnover of dopamine at PND14 was detected in the cocaine groups. All quantitative parameters reached normal values, in all groups, at PND90. These results show that, during the critical periods in which catecholamines can influence the development of neurons, cocaine transiently affects the pattern of dopaminergic neurons in the retina. This may have functional importance due to the role of this neurotransmitter as a regulatory and/or trophic factor in developing neuronal circuitries.
Experimental Eye Research 07/1996; 62(6):697-708. · 3.26 Impact Factor
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ABSTRACT: The use of drugs of abuse--e.g., cocaine--during pregnancy has been associated with abnormalities of the visual system. The authors studied the effects of prenatal exposure to drugs of abuse, especially cocaine, on the vascular system of the retina in newborn infants and in an experimental model in the rat.
The animal study was conducted in pregnant Wistar rats injected subcutaneously with cocaine hydrochloride (60 mg/kg body weight/day) from gestation days 8 to 22. Male offspring were killed at postnatal days 7, 14, and 30 and perfused with fixative, and the retinas were dissected and processed for microscopic observation. The ophthalmologic observations were conducted in a population of newborn infants born to women who abused many drugs during pregnancy and in a control group of women with no history of illicit drug use.
Vascular disruptive lesions were seen after prenatal exposure to cocaine in the rat: round intraretinal hemorrhages, ischemic and hypoperfused areas located at the temporal part and often extending from the posterior pole to the periphery of the retina. The ophthalmologic observation of the newborns showed a higher incidence of vascular disruptive lesions in infants in whom exposure to drugs of abuse was affirmative during pregnancy. In the cases in which cocaine consumption was reported, they consisted in blot full-thickness hemorrhages with rounded domed contours suggestive of venous occlusion and retinal ischemia, very similar to the lesions seen in the animal model. These hemorrhagic lesions, morphologically similar to neonatal retinal hemorrhages, had a higher incidence than in controls; they also took longer to resolve when compared with the reabsorption time of the neonatal hemorrhages due to birth trauma and the hemorrhagic lesions in newborns of mothers in whom consumption of other drugs--but not cocaine--were reported.
A topographic and morphologic parallelism can be established between the retinal vascular alterations found in humans consuming cocaine and in the animal model of prenatal exposure to this drug of abuse; although findings from animal studies may be difficult to apply directly to humans, these data strongly support that cocaine can be a causal factor for the occurrence of retinal vascular disruption in newborns.
Retina 02/1996; 16(5):411-8. · 2.81 Impact Factor
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ABSTRACT: There is increasing evidence that early exposure to psychostimulants exerts long-lasting effects on the central nervous system. Yet, analysis of the body weight gain and volumetric determinations of brain areas have not been performed by comparing the effects of neonatal exposure to cocaine and amphetamine. Male (Wistar) rats were given cocaine hydrochloride (15 mg/kg body weight/day), D-amphetamine sulphate (25 mg/kg body weight/day) or saline, s.c., twice daily, from postnatal day (PND) 1 to 30. The experimental design used random permuted blocks of 4 males per litter -9 litters for body weight gain evolution and 9 for the analysis of body, brain and cerebellum at PND30. Volumes of the hippocampal formation were calculated in horizontal serial sections of celloidin embedded material from 6 animals per group. The analysis of body weight gain evolution was performed using discriminant functions and allowed the separation of the amphetamine group from the remainder and the control from the psychostimulants group; weight gain in PND 24-30 period presented the highest discriminating power. The mean volume of the hippocampal formation was lower in the psychostimulants group, and the differences were significant in the molecular layer of the dentate gyrus of cocaine and amphetamine exposed animals when compared with the controls.(ABSTRACT TRUNCATED AT 250 WORDS)
Brain Research 09/1993; 619(1-2):137-45. · 2.73 Impact Factor
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British Journal of Ophthalmology 05/1993; 77(4):248-50. · 2.90 Impact Factor
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ABSTRACT: Familial amyloidotic polyneuropathy (FAP) is a hereditary disease which may present a wide range of ocular manifestations. Glaucoma is amongst the most serious complications of FAP. We report the results of ultrastructural study of the trabecular meshwork in a glaucomatous patient with the Portuguese form of FAP. This study showed that there was marked anatomical disruption of the uveoscleral, cornoscleral meshworks and juxtacanalicular tissue characterized by (a) accumulation of amyloid fibrils in the intertrabecular spaces; (b) degeneration of the endothelial cells; (c) homogeneous and/or multilayered plaques of basement membrane-like material loading the intertrabecular spaces or protruding to the lumen of the Schlemm's canal; and (d) degeneration of unmyelinated nerve fibres. These morphological changes and an analysis of the literature suggest that mechanical and neuropathic events can be co-existing factors which enhance the resistance to aqueous humour outflow, leading to increased intraocular pressure and glaucoma in the Portuguese form of FAP.
Albrecht von Graæes Archiv für Ophthalmologie 04/1993; 231(3):131-5. · 2.17 Impact Factor
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ABSTRACT: The effects of neonatal exposure to cocaine upon the structure of the visual system are poorly understood despite the evidence of eye abnormalities in infants exposed in utero to cocaine. We previously demonstrated alterations in the optic nerve of rats exposed neonatally to cocaine, although no changes were detected in the number of its axons. This study was undertaken to investigate the retinal ganglion cell layer and the size distribution of the optic axons, in an attempt to assess further changes in the visual pathways. Groups of rats (Wistar strain) were given subcutaneous injections of cocaine hydrochloride (15 mg kg-1 body weight day-1) divided into two daily doses, from the day following birth until postnatal day 30 Controls were given subcutaneous saline throughout the same experimental period. Per group, five animals from three different litters were evaluated morphometrically. Following perfusion with aldehydes, samples from the median ventral and dorsal parts of the retina and the optic nerves were processed for electron microscopy. Morphometric techniques at light and electron microscopic levels allowed us to determine the following. (a) In the optic nerve: (1) frequency size-distribution of myelinated nerve fibres; and (2) number of myelin sheaths per fibre. (b) In the retina: (1) thickness of the layers; (2) frequency size-distribution of ganglion layer neurons; (3) mean cell nuclear size; and (4) packing density of ganglion cell layer neurons.(ABSTRACT TRUNCATED AT 250 WORDS)
Experimental Eye Research 03/1993; 56(2):199-206. · 3.26 Impact Factor
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Cornea 10/1992; 11(5):486-9. · 1.73 Impact Factor
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ABSTRACT: We determined the effects of cocaine hydrochloride (15 mg/kg body weight/day) or amphetamine sulfate (25 mg/kg body weight/day) on the optic nerve in groups of rats exposed from postnatal day 1 to 30. Qualitative and quantitative studies of cross-sections of the optic nerves showed different patterns of organization, namely the presence of degenerative features in drug-treated animals and significant differences in the proportion of the nerve occupied by glial cells and their processes and nerve fiber bundles. No significant differences of the total number of fibers were found. Taken together, these data indicate that the optic nerve is vulnerable to early exposure to cocaine and amphetamine which cause developmental changes in this link of the visual pathways.
Ophthalmic Research 02/1991; 23(6):295-302. · 1.56 Impact Factor
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ABSTRACT: The effects of chronic alcohol consumption and withdrawal on the organization of the basal dendrites of layer III pyramidal cells of the prelimbic cortex were studied in groups of rats fed on alcohol for 6 or 18 months, and in a group fed for 12 months, then switched to water for a further 6 months (withdrawal group). Three-dimensional analysis of the dendritic arborizations showed an age-dependent increase in several dendritic parameters, but a net stability was found in the metrical parameters between alcohol-fed and respective control rats. Conversely, a dendritic impoverishment occurred in the withdrawal group. The linear density of dendritic spines remained stable in all groups studied. Together with the previously found marked loss of the neurons after alcohol consumption and withdrawal, these findings point to a decrease in the available targets for afferents and therefore to the presence of probable functional alterations as a consequence of those in the connectivity patterns of the prelimbic area occurring under these conditions.
Alcohol and Alcoholism 02/1990; 25(5):467-75. · 2.95 Impact Factor
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ABSTRACT: It was previously demonstrated that after prolonged alcohol consumption, dendrites might display either degenerative or plastic changes according to the central nervous system areas studied. Furthermore, and rather unexpectedly, we also found that withdrawal from alcohol led to a decrease of the relative number of granule cells in the fascia dentata. Thus, it seemed worthwhile to quantify, using a semiautomatic measuring system, the dendritic arborizations of hippocampal granule cells of rats alcohol-fed for 12 months followed by 6 months of abstinence and compare the results with age-matched control and alcohol-fed groups. The results indicate smaller dendritic trees in the abstinent group when compared with the higher values of the dendritic parameters found in alcohol-fed rats.
Alcoholism Clinical and Experimental Research 01/1990; 13(6):837-40. · 3.34 Impact Factor
