Antilithiatic effect of Asparagus racemosus Willd on ethylene glycol-induced lithiasis in male albino Wistar rats

The ethanolic extract of Asparagus racemosus Willd. was evaluated for its inhibitory potential on lithiasis (stone formation), induced by oral administration of 0.75% ethylene glycolated water to adult male albino Wistar rats for 28 days. The ionic chemistry of urine was altered by ethylene glycol, which elevated the urinary concentration of crucial ions viz. calcium, oxalate, and phosphate, thereby contributing to renal stone formation. The ethanolic extract, however, significantly (p < 0.05) reduced the elevated level of these ions in urine. Also, it elevated the urinary concentration of magnesium, which is considered as one of the inhibitors of crystallization. The high serum creatinine level observed in ethylene glycol-treated rats was also reduced, following treatment with the extract. The histopathological findings also showed signs of improvement after treatment with the extract. All these observations provided the basis for the conclusion that this plant extract inhibits stone formation induced by ethylene glycol treatment.     

Antidepressant activity of Asparagus racemosus in rodent models

Asparagus racemosus Linn. (AR) is an Ayurvedic rasayana used as an adaptogen. Adaptogenic drugs are those which are useful as anti-stress agents by promoting non-specific resistance of the body. Although, the adaptogenic effect of AR is well documented, its use in psychological disorders like depression is not scientifically evaluated. Hence, the present investigation evaluates the antidepressant effect of methanolic extract of roots of AR (MAR) standardized to saponins (62.2% w/w). Rats were given MAR in the doses of 100, 200 and 400 mg/kg daily for 7 days and then subjected to forced swim test (FST) and learned helplessness test (LH). The results show that MAR decreases immobility in FST and increases avoidance response in LH indicating antidepressant activity. In behavioral experiments, MAR increased the number of head twitches produced by 5-HTP and increased clonidine-induced aggressive behavior indicating facilitatory effect on both serotonergic and adrenergic systems respectively. However, MAR had insignificant effect on l-DOPA-induced aggressive behavior indicating absence of activity on dopaminergic system. MAR also reversed changes to the endogenous antioxidant system induced by FST. Thus, MAR has significant antidepressant activity and this effect is probably mediated through the serotonergic and the noradrenergic systems and augmentation of antioxidant defenses.     

Immunomodulatory active steroidal saponins from Asparagus racemosus

Asparagus racemosus is used in the Indian traditional system of medicine for improving the general state of health and stress-related immune disorders. Most of the synthetic chemotherapeutic agents available today are immunosuppressants and exert variety of side effects. To overcome these undesired effects of chemotherapeutic agents, botanical-based immunomodulators are often employed as adjuvant therapy. In the present study, immunomodulatory activity of two steroidal saponins shatavaroside A (1) and shatavaroside B (2), isolated from Asparagus racemosus, have been evaluated using polymorphonuclear leucocyte function test. The activity was further confirmed using more sensitive assays such as nitroblue tetrazolium, nitrous oxide, and chemiluminescence assays. Both steroidal saponins were found active at nano concentration (5 ng/ml) and can act as potent immunostimulants.     

Mechanism of ulcerogenic activity of reserpine in albino rats

Reserpine-induced gastric ulceration was significantly prevented by α-adrenoceptor blockers but not by propanolol or by bilateral adrenalectomy. Intracerebroventricular (i.c.v.) administration of reserpine as well as tetrabenazine failed to induce ulceration in albino rats. Pretreatment with 6-hydroxydopamine or atropine methyl nitrate protected the animals from the ulcerogenic activity of reserpine.     

Role of catecholamines in the hypothermic activity of cannabis in albino rats

Role of brain monoamines in the hypothermic activity of cannabis resin (CI) in albino rats was studied using agents which influence monoamine synthesis, storage, release, reuptake, metabolism and receptor activity and monoaminergic neuronal activity. Delta-9-tetrahydrocannabinol content of resin was estimated to be 17%. Reserpine was used for comparison. CI was given orally in the dose of 50 mg/kg. Nialamide (NM) and -methyl-metatyrosine (MMT) caused slight hyperthermia. p-Chlorophenylalanine (PCPA), -methyl-p-tyrosine (MPT), 5,6-dihydroxytryptamine (DHT, icv) and 6-hydroxydopamine (6-HD, icv) had no effect on body temperature. -Methyldopa (m-Dopa), diethyldithiocarbamate (DDC), DDC with l-Dopa, gammabutyrolactone (GBL), phentolamine (PHENT), phenoxybenzamine (PBZ), propranolol (PROP) and imipramine (IMP) produced hypothermia. Hypothermic activity of CI was potentiated by NM and PCPA, unaffected by DHT and m-Dopa, blocked by MMT, MPT, 6-HD, GBL, PHENT, PROP and chlorpromazine (CPZ), inhibited by DDC, DDC and l-Dopa and PBZ. CI induced hyperthermia in tolerant rats could be reversed to hypothermia by IMP. Reserpine hypothermia was blocked by NM, MPT, 6-HD and CPZ. There was a partial cross tolerance between cannabis and reserpine. Studies indicate that the hypothermic activity of CI similar to that of reserpine is mediated through central catecholamines and not 5-HT, and that noradrenaline is involved and not dopamine. However, the mechanism of action of cannabis and reserpine on nor-adrenergic neurone seems to be different.     

The effect of vagotomy and hydrocortisone administration on pulmonary surfactant activity in adult albino rats

The role of vagus and hydrocortisone in the regulation of lung surfactant was studied in adult albino rats. Dynamic surface tension and phospholipid content were measured in the lung wash for estimating surfactant activity. The results indicate that vagotomy significantly decreases the surfactant activity whereas hydrocortisone does not alter it. But when hydrocortisone was administered prior to vagotomy it could prevent the decrease in surfactant activity. Thus it is concluded the regulation of lung surfactant in the adult lung is mainly by vagus nerve and hydrocortisone as such has no role but in the absence of vagal regulation hydrocortisone could maintain normal lung surfactant activity.     

Antiulcer activity of levcromakalim and nicorandil in albino rats: a comparative study

The objective of the present study was to investigate and compare the antiulcer effect of potassium channel openers, nicorandil and levcromakalim in the models of ulcer induced by pylorus ligation, aspirin and water immersion plus restraint stress in albino rats. Levcromakalim (250 microg/kg) and nicorandil (10 mg/kg) were administered intraduodenally immediately after pylorus ligation. Ulcer index was determined and gastric juice was subjected to analysis of total acid output (TAO) and pH. In aspirin-induced gastric ulcer model, the drugs were administered orally 30 min prior to noxious challenge, and in water immersion restraint stress model, the drugs were administered orally and ulcer index was determined. A significant reduction in ulcer index was observed after treatment with both potassium channel openers in all the gastric ulcer models. In pylorus-ligated rats, a significant decrease in TAO was noted. The conclusion is that potassium channel openers possess antiulcer activity. Antiulcer activity of levcromakalim is better than nicorandil but comparable to that of cimetidine. The antiulcer action of potassium channel openers is mediated partially by a decrease in gastric acid secretion, increase in gastric mucosal resistance and improvement in gastric mucosal blood flow.     

Toxicological effects of cypermethrin on female albino rats

A study was undertaken to evaluate the effects of cypermethrin on reproduction of female albino rats. The experimental rats were fed cypermethrin at 50 mg/kg b. wt. continuously for a period of 2 and 4 weeks. Feed and water intake was also noted daily for control, vehicle treated and cypermethrin-treated rats. It was observed that there was no effect on feed and water intake in treated rats as compared to the control group. Chronic exposure to cypermethrin for 4 weeks resulted in loose fecal pellets and hyperirritability in the treated rats. Treatment related mortality also occurred at the 4(th) wk of treatment. Significant changes in body weight and various organ weights due to cypermethrin were observed along with disruption of estrous cycle in rats. The body weight gain in treated rats was lower at both 2 and 4 weeks as compared to the control rats. The weight of liver and spleen decreased, while that of kidneys increased as compared to the control rats. Thyroid and adrenal showed increase in weight at both 2 and 4 weeks of treatments.     

Effect of foot-electroshock stress on cholinergic activity, tissue glycogen and blood sugar in albino rats

The immediate or 24 hr delayed effects of 1-day (1-DS) or (7-DS) foot-electroshock stress in albino rats were studied on cardiac acetylcholine (ACh), blood and cardiac cholinesterase (ChE) activities, cardiac, hepatic and muscle glycogen contents and blood sugar concentrations. The effects of physostigmine (PHY), atropine, 6-hydroxydopamine (6-HD), vagotomy and adrenalectomy on 1-DS induced changes were also studied. 1-DS produced an increase in cardiac ACh content which lasted for 24 hr but repeated stress showed phenomenon of adaptation. There seems to be activation of autonomic cholinergic system in stress. 1-DS and 7-DS produced a short-lived inhibition of blood ChE activity and 7-DS also of cardiac ChE activity. Inhibition of ChE activity was probably related to release of adrenaline from adrenal medulla. 1-DS produced hepatic and muscle glycogenolysis with slight hypoglycaemia but without any effect on cardiac glycogen. Following repeated stress there was a phenomenon of adaptation. The hepatic and muscle glycogenolysis produced by stress is due to the release of adrenaline from adrenal medulla. Normally functioning cardiac cholinergic system seems to have a protective effect on heart against stress, in the absence of which cardiac glycogenolysis is induced by stress.     

Chemical analysis reveals the botanical origin of shatavari products and confirms the absence of alkaloid asparagamine A in Asparagus racemosus

Shatavari??a famous Ayurveda materia medica used mainly as a tonic for women??is distributed in health food products all over the world. The Ayurvedic Pharmacopoeia of India identifies the botanical origin of shatavari as the tuberous root of Asparagus racemosus. We recently investigated by DNA analysis the botanical origin of shatavari products on the Japanese market. The results suggested that their botanical origin was Asparagus; however, species identification was difficult. In this study, we analyzed steroidal saponins, including those specific to this plant, in these products and confirmed their origin as A. racemosus. Next, alkaloid analyses of an authentic A. racemosus plant and these products were performed, because several papers have reported the isolation of a pyrrolo[1,2-a]azepine alkaloid, asparagamine A, from this plant. Our results suggest that neither plant material nor products contained asparagamine A. It has been pointed out that Stemona plants are sometimes mistaken for shatavari, because their tuberous roots have a similar shape to that of A. racemosus, and pyrrolo[1,2-a]azepine alkaloids are thought to be Stemona-specific. These data strongly suggest that A. racemosus does not contain asparagamine A, and that previous isolation of asparagamine A from materials claimed as originating from A. racemosus was likely caused by misidentification of Stemona plants as A. racemosus.     

Hepatoprotective activity of Stereospermum suaveolens against CCl4-induced liver damage in albino rats

The present study aims to evaluate the hepatoprotective activity of Stereospermum suaveolens DC (Bignoniaceae). Hepatoprotective activity is studied by carbon tetrachloride (CCl₄)-induced liver damage in albino rats. The degree of protection in this activity has been measured by using biochemical parameters such as serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), alkaline phosphatase (ALP), total bilirubin, LDL-cholesterol and SOD, CAT, GSH, total thiols, NO, and lipid peroxidation in liver tissue homogenate. The results suggest that the methanol stem bark extract of Stereospermum suaveolens at the doses 125, 250, and 500?mg/kg and reference standard Liv-52 treated group produced significant (p <0.001) hepatoprotection against CCl₄-induced liver damage by decreasing the activities of serum enzymes, bilirubin and lipid peroxidation. The extract significantly (p <0.001) increased levels of SOD, CAT, GSH and total thiols, as compared to control group. Histopathological studies further substantiate the protective effect of the extract. It was concluded that methanol stem bark extract of Stereospermum suaveolens showed effective hepatoprotective activity.     

Influence of testosterone on morphine analgesia in albino rats

Pain threshold for thermal stimulus after morphine, naloxone alone and naloxone in combination with morphine was studied in male rats before and after three days treatment with testosterone. It was also determined 15 days after gonadectomy and administration of testosterone in such rats. There was significant reduction in morphine analgesia after administration of testosterone and also after gonadectomy. Naloxone increased the pain threshold in gonadectomised rats and it enhanced morphine induced analgesia instead of antagonising it. Naloxone, however, had no effect on morphine analgesia in testosterone treated control rats and gonadectomised rats.