Shripad Deshpande

• MD, PhD
• Professor at Nobel Medical College Teaching Hospital

Introduction: Peripheral Vascular Disease (PVD) is an important public health problem, due to its insidious course and the associated co-morbidities. Obesity has been implicated as one of the risk factor besides others. However, the reports on obesity are not consistent. Aim: To assess the association between central obesity and PVD along with othe...

BACKGROUND: Venous hypertension in the lower limb is predisposing factor for the chronic venous insufficiency and resultant skin changes. In a normal limb, during ambulation, there is a fall in lower limb venous pressure as the calf muscle pump and unidirectional valvular activity propel the blood from the lower limbs to the heart. Failure of this...

Introduction: Bisphenol A (BPA), an estrogenic compound is used in the manufacturing of plastics and also as coating for the inner linings of food packaging containers. It is reported to be an endocrine disruptor and produce toxicity in various organs. Since BPA exposure mainly occurs in the form of oral ingestion in humans, the present study was p...

Red scorpion (Mesobuthus tumulus) envenomation is a common life threatening medical problem in India. Pulmonary edema and decrease in lung compliance is a common manifestation after scorpion envenomation. In the present study, role of vagus in mediating Mesobuthus tamulus (MBT) venom-induced alteration in pulmonary water content and compliance was...

Background Bisphenol A (BPA), a chemical used in the manufacture of plastics, has toxic effects on various systems of the human body including the reproductive system. BPA possesses estrogenic activity and is implicated in altering oogenesis, ovulation, and fertility. In addition to ovulatory changes, uterine contractility is an important factor fo...

Aims: Lignocaine is used during intrapartum and postpartum period but there are conflicting reports regarding the effect of lignocaine on uterine contractility. Therefore, this study was undertaken to delineate the effect of lignocaine on uterine contractility and the underlying mechanisms. Main methods: The in vitro contractions were recorded f...

Acute respiratory distress syndrome (ARDS) is a common clinical syndrome of acute lung injury with considerable mortality rate of 26-58%. Oleic acid (OA)-induced lung injury that reproduces the early exudative phase of ARDS is an established experimental model of acute lung injury in animals. In this study, we examined the role of antihistaminic dr...

Background: The autonomic changes and cardiorespiratory changes seen in vascular disorders are suggested to be mediated reflexly by the activation of perivascular nociceptors. The role of prostaglandins, vanilloid receptor 1, 5-hydroxytryptamine type 3, and kinin receptors is well established. Aims and Objectives: This study was conducted to unders...

Background: Acute respiratory distress syndrome (ARDS) is a severe inflammatory condition. Our earlier studies have characterized oleic acid (OA)-induced rat model of ARDS which was exacerbated by indomethacin (prostaglandin [PG] synthesis inhibitor). Aim and Objectives: The role of PGs in ARDS is ill defined as the results of earlier studies are c...

Background: Mesobuthus tumulus (red scorpion, MBT) envenomation is a serious health problem in tropical countries and is responsible for high morbidity and mortality. Aims and Objectives: Earlier reports about the role of vagus in producing MBT venom-induced toxicity are conflicting. Therefore, in this study, the role of vagus in MBT venom-induced...

Background: Bisphenol A (BPA), a chemical used in the manufacture of plastics, has toxic effects on reproductive, developmental, and metabolic systems. It is implicated as a causative factor for infertility. The uterine and tubal contractility play a vital role in fertilization and implantation of zygote. The chronic exposure to BPA on myometrial c...

Ischemia depresses the spinal Ia-α motoneuron synaptic transmission via NMDA dependent mechanism. We postulated that glutamate transporter inhibitor (DL-threo-β-hydroxy aspartate, THA) advances the ischemia-induced depression. The experiments were performed on isolated, hemisected spinal cord from 4-6 day old rats. The stimulation of a dorsal root...

Objective: Intra-arterial injection of Mesobuthus tamulus (BT) venom produces reflex vasosensory responses modulating cardiorespiratory parameters in albino rats. The present study was conducted to understand the role of kinin receptors in modulating vasosensory reflexes evoked by BT venom. Materials and Methods: In urethane-anesthetized rats, trac...

Acute respiratory distress syndrome (ARDS) is an acute fulminant condition associated with acute lung injury and inflammation leading to hypoxemia, pulmonary edema and respiratory failure. Even though prostaglandins are inflammatory mediators, the role of prostaglandins in ARDS is still not clear. Therefore, we examined the involvement of prostagla...

Appendicitis is a cause of health concern in all age and sex worldwide. Alteration in appendicular peristalsis/contractility has been implicated as a precipitating factor in appendicitis. But, the neurotransmitters involved in the contractility of normal human vermiform appendix are not well understood. The present study was undertaken to investiga...

Adult respiratory distress syndrome (ARDS) is a clinical condition associated with high mortality. Prostaglandins are involved in the pathophysiology of ARDS but the results of earlier studies are not conclusive. Therefore, this study was aimed to determine the role of misoprostol (Prostaglandin E1 agonist) in oleic acid (OA)-induced ARDS in rats....

Mesobuthus tamulus (MBT) venom and oleic acid (OA) have been shown to produce acute respiratory distress syndrome (ARDS) involving different mechanisms. The role of vagally mediated anti-inflammatory pathway in ARDS is poorly understood. Therefore, the effects of vagal efferent stimulation on these two models of ARDS were examined. Experiments were...

Background and purpose: Postural impairments and functional limitations are linked to osteoarthritis knee adults. The purpose of this study was to identify the balance & postural impairments in osteoarthritis adults and compare the efficacy of two treatment strategies, Structured Neuromuscular Postural Training (SNPT) with conventional treatme...

The present study was undertaken to determine whether acute respiratory distress syndrome (ARDS) is produced after Mesobuthus tamulus (MBT) envenomation and compared it with oleic acid (OA)-induced ARDS. The trachea, jugular vein and femoral artery were cannulated in anesthetized adult rats. Lethal dose of MBT venom (5 mg/kg) or OA (75 μL) was admi...

Bisphenol-A (BPA), a toxic chemical from plastics, is known to produce locomotor abnormalities which may imply the alteration in synaptic activity at Ia-α motoneuron synapse also. However the effect of BPA on this synapse is not known. Therefore, this study was undertaken to examine the effect of BPA on reflexes originating at Ia-α motoneuron synap...

Capsaicin, a nociceptive agent produces triphasic pressure response in rats. The mechanisms underlying capsaicin-induced pressure responses are not clear. Therefore, the present study was undertaken to determine the mechanisms involved in capsaicin – induced pressure responses. The trachea, jugular vein and femoral artery were cannulated in anaesth...

Bisphenol A (BPA) attenuated phenylbiguanide (PBG)-induced cardio-respiratory reflexes involving decreased vagal afferent activity. BPA leaches out from plastics thus it is expected that chronic exposure to plastic boiled (PBW) water will also produce similar changes. Therefore, the present study was undertaken to evaluate the effects of chronic in...

The current study was undertaken to compare the effects of pulmonary oedema producing toxin (PO-Tx) isolated from Mesobuthus tamulus venom on cardio-respiratory reflexes with exogenously administered bradykinin (BK) and to delineate the type of BK receptors mediating these responses. Jugular venous injection of phenyldiguanide (PDG) in anaesthetize...

Animal studies using oleic acid (OA) model to produce acute respiratory distress syndrome (ARDS) have been inconsistent. Therefore, the present study was undertaken to establish an acute model of ARDS in rats using OA and to characterize its effect on cardio-respiratory parameters and lethality. The trachea, jugular vein and femoral artery of anest...

The erect posture and bipedalism in humans has evolved at cost of compromise of abilities in meeting some challenging demands of physiology. Counter adaptive mechanisms have emerged and keen understanding of their pliability is crucial to health and management of disease. Several features of human placenta are distinctive in providing advantage for...

Basic biomedical sciences form foundation for enlightened rational clinical practice and provide substance for innovation and advance. Tooth eruption is highly complex yet finely regulated process of developmental biology. Integration of local, regional and systemic mechanisms is uniquely displayed in eruption physiology. Serial and reciprocal gene...

Intra-arterial (i.a.) injection of Mesobuthus tamulus (BT; 1 mg/kg) venom produces reflex vasosensory responses in albino rats. Present study was conducted to understand the role of des-arg (B1 receptor antagonist) and hoe-140 (B2 receptor antagonist) modulating cardiorespiratory parameters evoked by BT venom producing the vasosensory responses. Al...

Capsaicin is used to evoke pulmonary C reflexes and produces complex pressure responses along with apnea/tachypnea, and bradycardia. In the present study, the mechanisms involved in capsaicin-induced pressure responses were explored. Tracheal, jugular venous, and femoral artery cannulations were performed in anesthetized adult rats. Blood pressure,...

Surfactant is an agent that decreases the surface tension between two media. The surface tension between gaseous-aqueous interphase in the lungs is decreased by the presence of a thin layer of fluid known as pulmonary surfactant. The pulmonary surfactant is produced by the alveolar type-II (AT-II) cells of the lungs. It is essential for efficient e...

Bisphenol A (BPA), a toxic chemical released from plastics, produces respiratory arrest and hypotension after a latency. The latency was similar to the reflex apnoea induced by the vagal C fibre stimulation. Therefore, the present study was undertaken to examine the effects of chronic and acute exposure to BPA on cardio-respiratory reflexes elicite...

Phenylbiguanide (PBG) and capsaicin evoke cardiorespiratory reflexes utilizing two separate pathways. It is known that Indian Red Scorpion (Mesobuthus tumulus; MBT) venom augments PBG (5-HT(3)) responses but, the effect of MBT venom on capsaicin (TRPV1)-induced response is not known. Therefore, the present study was undertaken to ascertain whether...

Bisphenol A (BPA), an estrogenic compound, is used in manufacturing plastics and is known to produce toxic effects on various systems in man and animals. Since the use of plastics in day-to-day life is increasing, exposure to BPA will also increase. Therefore, this study was undertaken to determine the median lethal dose (LD50) of BPA via intraperi...

Bisphenol-A (BPA), a toxic chemical from polycarbonate plastics, is known for behavioural and neural abnormalities. These neuro-behavioural changes reflect the changes in neural activity. However the effect of BPA on nerve action potential is not available. Therefore, present investigation was undertaken to study the effect of BPA on compound actio...

Bisphenol A (BPA) is used in manufacturing plastics. Even though BPA is reported to produce reproductive and behavioral toxicity in experimental animals, the direct effect of BPA on the cardiovascular system is not known. The present study was therefore undertaken to evaluate the effect of BPA, on spontaneously beating rat right atrial preparations...

Glutamate is a putative neurotransmitter at Ia-alpha motoneuron synapse in the spinal cord and mediate the action via N-methyl-D-aspartate (NMDA) and a-amino-3-hydroxy-5-methyl-4-isoxazole-propionate (AMPA) receptors. Since NMDA receptors are not involved in M. tamulus Pocock (MBT) venom-induced depression of spinal monosynaptic reflex (MSR), the p...

The present study was undertaken to evaluate the role of nitric oxide (NO) in Mesobuthus tamulus (MBT) venom-induced depression of spinal reflexes. Experiments were performed on isolated hemisected spinal cords from 4 to 6day old rats. Stimulation of a dorsal root with supramaximal strength evoked monosynaptic (MSR) and polysynaptic reflex (PSR) po...

Pulmonary edema is a consistent feature of Mesobuthus tamulus (MBT) envenomation. Kinins, prostaglandins and other inflammatory mediators are implicated in it. Since, histamine also increases capillary permeability, this study was undertaken to evaluate whether MBT venom utilizes histamine to produce pulmonary edema and augmentation of cardio-respi...

The objective of our consensus process was to develop a unique classification of the natural history of scorpion stings and their clinical signs and symptoms. The technique used was an adapted Delphi approach completed by a nominal group meeting. Researchers included in a study received a questionnaire in which we listed all terms used in published...

Role of 2-Deoxy-D-glucose (2-DG) in reversing the Indian red scorpion (Mesobuthus tamulus concanesis Pocock, MBT) venom-induced toxicity was examined. Femoral arterial pressure, ECG and respiratory movements were recorded in urethane anesthetized rats. Plasma glucose and serum insulin levels were also estimated. Intravenous injection of 5 mg/kg MBT...

Mesobuthus tamulus (MBT) venom is shown to depress the spinal reflexes through a mechanism unrelated to the NMDA receptors. 5-Hydroxytryptamine (5-HT) is another excitatory transmitter in the spinal cord therefore, the present study was undertaken to examine the involvement of 5-HT in the venom-induced depression of reflexes. The experiments were p...

The aim of present study was to prepare and evaluate buccal bioadhesive films of salbutamol sulphate (SS) for the treatment of asthma. The films were designed to release file drug for a prolonged period of time so as to reduce the frequency of administration of the available conventional dosage forms of SS. The different proportions of, sodium carb...

The aim of present study was to prepare and evaluate buccal bioadhesive films of salbutamol sulphate (SS) for the treatment of asthma. The films were designed to release the drug for a prolonged period of time so as to reduce the frequency of administration of the available conventional dosage forms of SS. The different proportions of sodium carbox...

Acute ingestion of large quantity of chili peppers (rich source of capsaicin) produced hypertensive crisis in a patient. The hypertensive response was explained on the basis of decreased vasodilator substance calcitonin gene-related peptide (CGRP) from sensory nerve terminals by capsaicin. Here we present our experimental observations in anaestheti...

Stimulation of pulmonary C fibre receptors by phenylbiguanide (PBG, 5-HT(3) agonist) produces hypotension, bradycardia and tachypnoea or apnoea. However, tachypnoeic or apnoeic responses are not consistent. Therefore, this study was undertaken to delineate the actions of PBG on respiration and compared with those evoked by capsaicin (TRPV1 agonist)...

Stings of Indian red scorpion (Mesobuthus tamulus, MBT) produce neurological abnormalities such as convulsions and paralysis. These parameters indicate the activity at alpha-motoneuron. The present study was therefore, undertaken to evaluate the effect of MBT-venom on spinal reflexes and the involvement of N-methyl-d-aspartate (NMDA) receptors. The...

Receptor subtypes involved in the 5-hydroxytryptamine (5-HT)-induced depression of synaptic transmission in neonatal rat spinal cords in vitro were evaluated in the absence or presence of Mg(2+) in the medium. Stimulation of a dorsal root evoked monosynaptic reflex potential (MSP) and polysynaptic reflex potential (PSP) in the segmental ventral roo...

Gastric dysfunctions are commonly seen after scorpion envenomation, and the underlying mechanisms are not clear. Therefore, the present study was undertaken to investigate the effect of Indian red scorpion (Mesobuthus tamulus, MBT) venom on gastric fundus muscle contraction and the underlying mechanisms involved. In vitro isometric contraction was...

The study was undertaken to evaluate the efficacy of multivitamin and micronutrient supplementation in azoospermic patients with maturation arrest. A total of 35 azoospermic patients showing maturation arrest on testicular biopsy were recruited in this study. The patients were divided into two groups. Untreated group (n=11) without any treatment an...

Nociceptive vascular reflexes evoked by scorpion venom modulate cardiorespiratory parameters involving vanilloid receptor 1 in anaesthetised rats.

Sildenafil, a drug used in the treatment of erectile dysfunction, is a phosphodiesterase 5A inhibitor that increases cyclic guanosine monophosphate (cGMP) levels. In addition to its vascular actions, sildenafil is also known to alter cardiac functions. This study was undertaken to elucidate the effect of sildenafil on cardiac contractility and the...

This study was performed to delineate the kinin (receptor)-dependent pathways in the Indian red scorpion (Mesobuthus tamulus; MBT) venom-induced pulmonary oedema as well as the augmentation of cardio-pulmonary reflexes evoked by phenyldiguanide (PDG). In urethane-anaesthetized adult rats, the effect of venom on the PDG reflex responses (blood press...

The objective of the present investigation is to study the involvement of nitric oxide (NO) in 3-nitropropionic acid (3-NPA)-induced depression of spinal reflexes. Experiments were conducted on preparations of hemisected spinal cord isolated from 4 to 8 day old rats. Stimulation of a dorsal root evoked reflex potentials (monosynaptic, MSR; polysyna...

Effect of 3-nitropropionic acid (3-NPA) and ischemia (glucose- and O2-free solution) on synaptic transmission in hemisected spinal cord from 4 to 8 day old rats was examined in vitro. Stimulation of a dorsal root (L3-5 segments) evoked monosynaptic (MSR) and polysynaptic reflex (PSR) potentials in the segmental ventral root. Superfusion of 3-NPA (0...

Role of G-protein coupled pathways in modulating the cardiotoxic effects produced by Indian red scorpion (Mesobuthus tamulus) venom were examined. The isometric contractions of spontaneously beating or paced (3.5 Hz) rat right atrial preparations in vitro were recorded. The cumulative concentration (0.01-3.0 microg/ml)-response of venom on spontane...

The present study was conducted to compare the time-related cardiorespiratory changes occurring after the injection of Mesobuthus tamulus (BT; 1 mg/kg) venom and capsaicin (1.2 ng/kg) in the peripheral end of femoral artery in urethane anaesthetised rats. Blood pressure (BP), electrocardiogram (for heart rate; HR) and respiratory movements were rec...

3-Nitropropionic acid (3-NPA) is a naturally occurring fungal toxin that leads to ATP-depletion by inhibiting mitochondrial succinate dehydrogenase and produces chemical anoxia. The present study was conducted to identify the involvement of inhibitory system in 3-NPA-induced depression of spinal reflexes. The monosynaptic (MSR) and polysynaptic ref...

The present study was undertaken to isolate 5-hydroxytryptamine (5-HT) from crude Indian red scorpion (Mesobuthus tamulus; MBT) venom as it has not been reported yet. Therefore, with the help of bioassay (using gastric fundus contractions) and fluorimetric assay methods, the 5-HT content of crude MBT venom (CV) was determined. The concentration of...

The involvement of 5-hydroxytryptaminergic (5-HTergic) system for the 3-nitropropionic acid (3-NPA)-induced depression of spinal reflexes was evaluated and compared with other energy deficiency condition (ischemia; glucose-free and O2-free). The monosynaptic (MSR) and polysynaptic reflex (PSR) potentials were recorded at ventral root by stimulating...

The present study was conducted to examine the role of phospholipase A(2) and prostaglandins in Indian red scorpion (Mesobuthus tamulus; MBT) venom-induced augmentation of cardiopulmonary reflexes elicited by phenyldiguanide (PDG). Trachea, femoral artery and jugular vein were cannulated in urethane anesthetized adult albino rats. The effect of jug...

2-Deoxy-D-Glucose (2-DG), a synthetic analogue of glucose, is used as an anticancer agent either alone or in combination with other tumor treatment protocols. The present study was conducted to identify the systemic effects of 2-DG on parameters of vital importance. The blood pressure, ECG and respiratory excursions were recorded in anesthetized ad...

Indian red scorpion (Mesobuthus tamulus; MBT) produces lethal stings and is a matter of concern in certain parts of India. MBT envenomation produces multi-systemic involvement, thus presents difficulty in the management. Symptomatic treatment has been practiced earlier that failed to relieve the toxic effects of the venom. Therefore, present manusc...

Intra-arterial (i.a.) injection of Indian red scorpion (Mesobuthus tamulus; BT) venom produces cardiorespiratory changes by involving perivascular receptors. The afferents involved in mediating these reflex responses are not known. The present investigation was conducted to examine the afferents mediating the vasosensory reflexes evoked by i.a. inj...

Indian red scorpion (Mesobuthus tamulus; MBT) envenomation produces various cardio-respiratory abnormalities including cardiac dysrhythmias. The underlying cell signaling pathways for the cardiac dysrhythmias produced by MBT venom are not known. The present study was therefore conducted to delineate the second messenger signaling pathways involved...

Marine dinoflagellate Ptychodiscus brevis toxin (PbTx), is known to produce toxic effects on cardiovascular system. The present experiments were conducted to evaluate the effect of synthetic phosphorus containing Ptychodiscus brevis toxin on spontaneously beating right atrium in vitro. The PbTx (0.84-84 microM) decreased the rate and force of right...

The kinins are implicated in the pathogenesis of scorpion envenomation. Therefore, this study was carried out to examine the involvement of kinins for the ECG abnormalities induced by M. tamulus concanesis, (BT) venom in anaesthetized rats. ECG was recorded using needle electrodes with limb lead II configuration. The PR interval, QRS wave pattern,...

The present study evaluated the influence of habitual sleep duration on episodic memory in a wakeful state. Episodic memory was assessed for auditory and visual processing pathways. A total of 96 medical students (53 male and 43 female, between the age group 18-23 years) accustomed to different sleep durations volunteered in the tests. The tests in...

The involvement of 5-hydroxytryptaminergic (5-HT) system for the Ptychodiscus brevis toxin (PbTx)-induced depression of spinal reflexes was evaluated. The reflex potentials were recorded at ventral root by stimulating the corresponding dorsal root in neonatal rat spinal cord in vitro. Superfusion of PbTx (2.8-84microM) depressed the monosynaptic (M...

Role of estrogen on cardiac dysrhythmia produced by Indian red scorpion (Mesobuthus tamulus) venom was examined using rat right atrial preparations in vitro. In females, the M. tamulus venom produced an increase, a decrease and an increase in rate at 0.03, 0.3 and 3 microg/ml of venom, respectively, producing N-shaped response curve, whereas no suc...

The roles of nitric oxide (NO) in 3-nitropropionic acid (3-NPA)-induced toxicity were investigated using in vivo and in vitro models. Chronic 3-NPA administration (10 mg/kg) to rats produced selective striatal lesions that were associated with abnormal motor and EMG activities. In these animals, there was loss of glial fibrillary acidic protein (GF...

Role of perivascular afferents for the cardiorespiratory alterations produced by Mesobuthus tamulus (BT) envenomation was examined in urethane-anaesthetized male rats. Blood pressure (BP), respiratory rate (RR) and heart rate (HR) were recorded after injecting BT venom/saline in the distal end of femoral artery for 60 min. In addition, paw oedema w...

Although, reconstructive surgeons are concerned about the perfusion pressure of the perforators in relation to survivability of the flap, there is hardly any literature regarding the actual measurement. In this study after ascertaining the accuracy of recording set up in experimental animal, the perfusion pressure of the perforators arising from th...

The experiments were conducted to identify the toxin that produces pulmonary oedema in Mesobuthus tamulus (BT) envenomed animals. Crude BT venom was subjected to Sephadex gel filtration (G-75) and the fractions were screened for optical density (OD), neurotoxicity (prolongation of compound action potential in frog sciatic nerve) and lethality. All...

Involvement of 5-hydroxytryptaminergic (5-HT) system for aglycemia- and ischemia-induced depression of the spinal reflexes was evaluated. The monosynaptic (MSR) and polysynaptic (PSR) reflex potentials were elicited in the ventral root by stimulating the corresponding dorsal root in an isolated spinal cord from neonatal rat. Superfusion of aglycemi...

The present investigation was undertaken to delineate the in vitro responsiveness of cholelithiatic gallbladders to cholecystokinin (CCK) and compared with those evoked by carbachol, histamine, or electrical stimulation. Gallbladder muscular strips (2-3 mm wide and 15-20 mm long) from patients undergoing cholecystectomy were used for recording the...

Role of aprotinin (kallikrein-kinin synthesis inhibitor) in preventing the cardio-respiratory toxicity induced by Mesobuthus tamulus (BT) venom was evaluated. The effects of BT venom (5 mg/kg) on mean arterial pressure (MAP), heart rate (HR), respiratory rate (RR), lung compliance and pulmonary water content were examined. BT venom produced alterat...

The effects of hypoxia (O2-free), aglycemia (glucose-free), ischemia (O2- and glucose-free) and chemical anoxia (by 3-nitropropionic acid; 3-NPA) were evaluated on the synaptic transmission in vitro. Stimulation of a dorsal root in hemisected spinal cord from neonatal rat, evoked monosynaptic (MSR) and polysynaptic reflexes (PSR) in the segmental v...

The present investigation was carried out to know the effect of Ca2+ on different peaks of compound action potential (CAP) representing the fibers having different conduction velocity. CAP was recorded from a thin bundle of nerve fibers obtained from desheathed frog sciatic nerve. Suction electrodes were used for stimulating and recording purposes....

The involvement of frequency-dependent depression (FDD) of synaptic transmission for the depressant action of the Ptychodiscus brevis toxin (PbTx) was investigated in neonatal rat spinal cord in vitro. The stimulation of a dorsal root by train of pulses (five stimuli) at different frequencies evoked potentials in the ventral root (monosynaptic refl...

The effects of in vitro aglycemia (glucose-free) and ischemia (glucose-free and O(2)-free) were examined on the dorsal root-evoked ventral root spinal monosynaptic and polysynaptic reflexes in neonatal rat spinal cords. Aglycemia and ischemia depressed the reflexes in a time-dependent manner and abolished them by 35 min. The depression by ischemia...

The protective action of R-(-)-deprenyl against the aglycemia (glucose-free) and the ischemia (glucose-free and O2-free)-induced changes in the synaptic transmission was investigated. The in vitro "glucose-free and O2-free" condition mimics in vivo ischemia where there is a deficiency of O2 and energy substrate, hence the term ischemia was used. Th...

In vitro models of anoxia have revealed severe changes in neuronal functions after ischaemia but not after aglycaemia, although hypoglycaemia produced severe neuronal dysfunctions sometimes leading to coma. The present study was therefore undertaken to examine and compare the effects of aglycaemia with that of ischaemia on synaptic transmission in...

The involvement of inhibitory transmitters for Ptychodiscus brevis toxin (PbTx)-induced depression of spinal synaptic transmission in neonatal rats was investigated. Stimulation of a dorsal root evoked monosynaptic reflex (MSR) and polysynaptic reflex (PSR) potentials in the segmental ventral root. The PbTx depressed the reflexes in a concentration...

Effects of Ptychodiscus brevis toxin (PbTx) analogs on the spinal synaptic transmission in neonatal rats in vitro were evaluated. PbTx1/PbTx2 had aromatic groups and PbTx3/PbTx4 had aliphatic groups. All the analogs depressed monosynaptic reflex (MSR) and polysynaptic reflex (PSR) in a concentration-dependent manner. The maximal depression of MSR (...

The effects of Ptychodiscus brevis toxin (PbTx) on the Ia-alpha motoneuron synaptic transmission in neonatal rat spinal cord in vitro was examined. The stimulation of a dorsal root evoked monosynaptic (MSR) and polysynaptic reflex (PSR) potentials in the segmental ventral root in Mg2+-free medium. Superfusion with PbTx (2.8-84 microM) depressed the...

The mechanisms underlying the action of Indian red scorpion Buthus tamulus (BT) venom-induced augmentation of cardiopulmonary reflexes elicited by intravenous injection of 5-HT were examined in urethane anaesthetized rats. The 5-HT produced a concentration-dependent increase in time-response area of bradycardiac response, with the responses at subm...