Evalution of anti-ulcer activity of Polyalthia longifolia (Sonn.) Thwaites in experimental animals

Objective:

To evaluate the anti-ulcer activity of ethanol extract of leaves of Polyalthia longifolia (Sonn.) Thwaites.

Materials and Methods:

The ethanol extract of Polyalthia longifolia was investigated for its anti-ulcer activity against aspirin plus pylorous ligation induced gastric ulcer in rats, HCl -Ethanol induced ulcer in mice and water immersion stress induced ulcer in rats at 300 mg/kg body weight.p.o.

Results:

A significant (P < 0.01, P < 0.001) anti ulcer activity was observed in all the models. Pylorous ligation showed significant (P< 0.01) reduction in gastric volume, free acidity and ulcer index as compared to control. It also showed 89.71% ulcer inhibition in HCl- Ethanol induced ulcer and 95.3% ulcer protection index in stress induced ulcer.

Conclusion:

This present study indicates that P. longifolia leaves extract have potential anti ulcer activity in the three models tested.     

Evaluation of anti-ulcer effect of amlodipine in gastric ulcer models in rats

Aims:

To study anti-ulcer effect of Amlodipine and compared it with ranitidine in indomethacin, alcohol and pyloric ligation-induced gastric ulcers in wistar rats.

Materials and Methods:

Gastric ulcers were induced in Wistar albino rats by oral administration of indomethacin (200 mg/kg), alcohol (80%, 1 ml/100 gm) and by pyloric ligation. Antiulcer activity of amlodipine (0.5 mg/kg, i.p.) was observed either alone or in combination with ranitidine (15 mg/kg, i.p.), on ulcer index, gastric pH and gastric volume. Statistical analysis was done by ANOVA and unpaired one tailed ‘t‘ test. P<0.05 was considered statistically significant.

Results:

Amlodipine produced significant (P<0.05) decrease in ulcer index and gastric pH as compared to control. It also produced significant (P<0.05) increase in gastric volume as compared to ranitidine. The anti-ulcer effects of ranitidine were significantly higher than that of amlodipine. Combination of amlodipine and ranitidine did not show significant increase in anti-ulcer activity as compared with ranitidine alone.

Conclusions:

Amlodipine produced significant anti-ulcer effects in all 3 experimental models. Amlodipine increased the volume of gastric secretions as compared to ranitidine.KEY WORDS: Amlodipine, ranitidine, ulcer index     

Evaluation of anti-ulcer activity of Samanea saman (Jacq) merr bark on ethanol and stress induced gastric lesions in albino rats

Objective:

To evaluate the antiulcer activity of Samanea saman (Jacq) Merr bark on ethanol and stress induced gastric lesions in albino rats.

Materials and Methods:

Gastric lesions were induced in rats by oral administration of absolute ethanol (5 ml/kg) and stress induced by water immersion. The antiulcer activity of methanolic extract of Samanea saman (Jacq) Merr bark (100 mg/kg, 200 mg/kg, 400 mg/kg) was compared with standard drugs. The parameters studied were ulcer index, gastric juice volume, pH, free acidity and total acidity.

Result:

Samanea saman (Jacq) Merr showed a dose dependent curative ratio compared to ulcer control groups. The extract at 400 mg/kg showed significant anti ulcer activity which is almost equal to that of the standard drug in both models. The volume of acid secretion, total and free acidity was decreased and pH of the gastric juice was increased compared to ulcer control group.

Conclusions:

The present study indicates that Samanea saman (Jacq) Merr bark extracts have potential anti ulcer activity.     

Determination of the antiulcer properties of sodium cromoglycate in pylorus-ligated albino rats

Objectives:

To study the ulcer protective property of sodium cromoglycate in pylorusligated rats and the biochemical role in ulcer protection by various biochemical tests.

Materials and Methods:

The ulcer protective effect of sodium cromoglycate was studied using a Pyloric Ligation Model using Wistar albino rats. The antiulcer effect of sodium cromoglycate 40 mg/kg b.w., i.p., was compared with the reference drug ranitidine 27 mg/kg b.w., i.p. The ulcer index was calculated and other biochemical parameters like free acidity, total acidity, pH, mucin, pepsin and volume of gastric juice were determined.

Results:

Pylorus ligation showed a significant (P < 0.01) reduction in gastric volume, free acidity, total acidity and ulcer index as compared to the control.

Conclusion:

Sodium cromoglycate has activity equipotent to ranitidine.     

Gastroprotective effect of Benincasa hispida fruit extract

Objectives:

The antiulcer activity of Benincasa hispida (Thunb.) Cogn. fruit was evaluated in rats against ethanol-induced gastric mucosal damage, pylorus ligated (PL) gastric ulcers, and cold restraint-stress (CRS)-induced gastric ulcer models.

Methods:

Petroleum ether and methanol extracts were administrated orally at the dose of 300 mg/kg, and omeprazole (reference standard) at the dose of 20 mg/kg. Ulcer index was common parameter studied in all the models. Further, vascular permeability was evaluated in ethanol model, and effect on lipid peroxidation, viz. melondialdehyde (MDA) content, superoxide dismutase (SOD), and catalase (CAT) levels were studied in CRS model.

Results:

Both the extracts produced significant reduction in ulcer index (P < 0.05) in all the models and the results were comparable with that of omeprazole-treated group. Further, significant reduction in vascular permeability (P < 0.05) was observed. In CRS model, MDA content was significantly reduced along with increase in CAT levels as compared to control group.

Conclusions:

Petroleum ether and methanol extracts of B. hispida possess significant antiulcer as well as antioxidant property.     

Effects of S-0509, a novel CCKB/gastrin receptor antagonist, on acid secretion and experimental duodenal ulcers in rats

Background:

S-0509, 2-[(tert-butoxycarbonylmethyl) [(m-(carboxy-phenyl)-ureidomethyl-carbonyl]] aminobenzo phenone, was developed as a potent and selective CCK_B/gastrin receptor antagonist that does not affect the central nervous system.

Methods:

We evaluated the effects of S-0509 on gastric acid secretion and duodenal ulcerogenic and healing responses in rats comparing it with L-365,260, another CCK_B/gastrin receptor antagonist.

Results:

S-0509 (0.1~10 mg/kg, i.d.) was able to dose-dependently decrease basal acid secretion and inhibit the acid secretory responses induced by both pentagastrin (60 μg/kg/h, i.v.) and peptone (10%, i.g.) but not histamine (4 mg/kg/hr, i.v.) or carbachol (60 μg/kg/h, i.v.). L-365,260 (10 and 30 mg/kg, i.d.) caused only partial a suppression of the acid secretory response to pentagastrin but not to other stimuli, including peptone treatment. On the other hand, a duodenal ulcerogen, mepirizole (200 mg/kg, s.c.) caused an increase in acid secretion and resulted in penetrating ulcers in the proximal duodenum, and these ulcers gradually healed over 3 weeks. S-0509 significantly inhibited both the acid secretory (> 1.0 mg/kg, i.d.) and ulcerogenic (> 3 mg/kg, p.o.) responses induced by mepirizole when it was given as a pre-treatment. It also promoted significantly the healing of these ulcers (> 3 × 2 mg/kg, p.o.) when it was given twice daily for 14 days. In contrast, L-365,260 (30 mg/kg) tended to reduce the severity of mepirizole-induced duodenal ulcers, with a slight inhibition of acid secretion, but it caused no influence on the healing response of these ulcers.

Conclusion:

These results confirmed that S-0509 is a selective CCK_B/gastrin receptor antagonist with potent antisecretory action in vivo conditions, and further demonstrated that this agent not only prevents the development of duodenal ulcers but also shows healing promoting action on duodenal ulcers, probably through the blockade of CCK_B/gastrin receptors.

     

A biochemical study on the gastroprotective effect of hydroalcoholic extract of Andrographis paniculata in rats

Aim:

The aim of the present study is to evaluate the gastroprotective effect of hydroalcoholic extract of Andrographis paniculata (HAEAP) in male albino wistar rats.

Materials and Methods:

Rats were pretreated with HAEAP (100,200,500mg/kg b. wt for 30 days) and then gastric ulcers were induced by ethanol, aspirin, pylorus ligation and cold restraint stress models. Ulcer score was determined in all the ulcer models. pH, gastric volume, titrable acidity, pepsin, mucin, myeloperoxidase, H⁺K⁺ATPase, thiobarbituric acid reacting substances (TBARS) and antioxidant enzyme activities were assayed in ethanol-administered rats.

Results:

The ulcer score was found to be low in HAEAP-pretreated rats. Among the doses studied, 200 mg/kg b.wt was found to be optimum for significant ulcer reduction. The test drug significantly reduced the acidity, pepsin concentration, myeloperoxidase and H⁺K⁺ATPase activities in ethanol-administered rats. The elevated TBARS and decreased glutathione (GSH) and mucin levels observed during ulcerogenesis were found to be altered in HAEAP-received animals.

Conclusions:

The ulcer preventing effect of HAEAP may partly be due to its regulating effect on H⁺K⁺ATPase activity and /or mucin preserving effects. The flavonoids present in the HAEAP might be responsible for the gastroprotective action probably by maintaining the antioxidants and thiol status in the gastrointestinal tract.     

Pro-ulcer effects of resveratrol in mice with indomethacin-induced gastric ulcers are reversed by l-arginine

Background and purpose:

Although resveratrol is currently being evaluated in pre-clinical studies as a potential cancer chemopreventive agent and cardiovascular stress-releasing compound, treatment with resveratrol severely delays healing of pre-existing gastric ulcers. Resveratrol treatment can also induce endothelial NOS (eNOS) expression. Here, we have attempted to modulate NO production via eNOS in order to alleviate the pro-ulcer effects of resveratrol.

Experimental approach:

Gastric ulcers were induced in mice with a single dose of indomethacin. The effects of pretreatment with l-arginine on the pro-ulcer effects of resveratrol in these mice were then assessed. We measured ulcer damage scores (DS), myeloperoxidase (MPO) activity, generation of prostaglandin E₂ (PGE₂) and NO, along with a gene expression study.

Key results:

Resveratrol significantly aggravated damage from indomethacin-induced gastric ulcers, and delayed healing, as shown by increased DS and MPO activity. The mRNA for cyclooxygenase (COX)-1, but not that for COX-2, was inhibited by resveratrol treatment, with reduced synthesis of PGE₂ by gastric tissue. However, resveratrol treatment induced eNOS gene expression and shifted the eNOS/iNOS balance. l-Arginine given before resveratrol in mice with indomethacin-induced ulcers significantly increased tissue NO synthesis and improved ulcer healing.

Conclusions and implications:

Exogenous l-arginine increased NO formation via raised levels of eNOS induced by resveratrol and protected against the pro-ulcer effects of resveratrol. Therefore, l-arginine might be useful for alleviation of the pro-ulcer side effects of resveratrol in patients.     

Adaptogenic effect of Morus alba on chronic footshock-induced stress in rats

Objective:

The objective of the present study was to evaluate the adaptogenic property of the ethyl acetate-soluble fraction of methanol extract of Morus alba roots against a rat model of chronic stress (CS).

Materials and Methods:

Rats were exposed to stress procedure for 21 days. The stress procedure was mild, unpredictable footshock, administered for 1 h once daily for 21 days. Rats were administered with the ethyl acetate soluble fraction of methanol extract of M. alba roots (25, 50 and 100 mg/kg p.o) 1 h before footshock for 21 days and behavioral parameters were evaluated for cognitive dysfunction and depression using elevated plus maze and despair swim test, respectively. On day 21, rats were sacrificed immediately after stress and blood was collected for biochemical estimation. The adrenal gland and spleen were dissected for organ weight and the stomach was dissected for ulcer score.

Results:

CS significantly induced cognitive deficit, mental depression and hyperglycemia and increased blood corticosterone levels, gastric ulcerations and adrenal gland weight, but decreased the splenic weight. Pre-treatments with the ethyl acetate soluble fraction of methanol extract of M. alba roots (25, 50 and 100 mg/kg, p.o.) significantly attenuated the CS-induced perturbations. Diazepam (1 mg/kg, p.o.) was used as the standard antistress drug.

Conclusion:

The results indicate that M. alba possesses significant adaptogenic activity, indicating its possible clinical utility as an antistress agent.     

Effects of a gastric antisecretory-cytoprotectant 2-methyl-8-(phenylmethoxy)imidazo[1,2-a]pyridine-3-acetonitrile (Sch 28 080) on cysteamine, reserpine and stress ulcers in rats

Prostaglandin E2 and carbenoxolone, putative cytoprotective agents, were tested in cysteamine, reserpine and stress ulcers in rats. In cysteamine-induced duodenal ulcer, PGE2 was inactive at 0.1 and 0.5 mg/kg p.o.; carbenoxolone at 100 mg/kg p.o. decreased the incidence but not the severity of the ulcer. PGE2 at 5.0 mg/kg p.o. and carbenoxolone at 300 mg/kg p.o. showed moderate effects, but the dosage also inhibited cysteamine-stimulated acid secretion. PGE2 (0.1 and 0.3 mg/kg p.o.) was inactive and carbenoxolone (100 and 300 mg/kg p.o.) further aggravated the gastric ulceration caused by reserpine or cold-restraint stress. In contrast, atropine (3 and 10 mg/kg p.o.) and cimetidine (30, 100 and 300 mg/kg p.o.) were active in all three ulcer models. But the results with cimetidine in stress ulcer were somewhat variable. 2-methyl-8-(phenylmethoxy) imidazo [1,2-a] pyridine-3-acetonitrile (Sch 28 080), a novel structure with both cytoprotective and antisecretory activity, was highly efficacious in cysteamine, reserpine and stress ulcers (1-30 mg/kg p.o.), which was presumably adequately accounted for by its potent antisecretory activity. It is concluded that cysteamine, reserpine and stress ulcers may not be appropriate models for testing the potential antiulcer effect of primarily cytoprotective compounds.     

脑室注射催产素对大鼠胃和十二指肠溃疡的作用

INTRODUCTION Central neurons that synthesize oxytocin are locatedin the supraoptic(SON) and paraventricular nuclei(PVN) of the hypothalamus. Magnocellular neurons inboth nuclei project to the posterior pituitary gland,     

Examination of the potential antiulcer activity of the calcium antagonist propyl-methylenedioxyindene. III. Lack of effect on cysteamine-induced duodenal ulcers in rats

Since propyl-methylenedioxyindene (pr-MDI) exhibits significant protective effects against stress-induced ulcers in rats at subcardiovascular doses (10-30 mg/kg, i.p.), the aim of the present study was to explore the effect of this intracellular calcium antagonist on cysteamine-induced duodenal ulcers at the same low doses. Duodenal ulcers were induced in rats with a single dose of cysteamine (425 mg/kg, s.c.), which produced an 80% ulcer incidence within 24 h without affecting gastric acid concentration. Administration of pr-MDI (10 and 30 mg/kg, i.p.) at 0, 6 and 12 h post-cysteamine did not afford protection against ulceration. On the other hand, atropine (10 mg/kg, s.c., administered at 0, 6 and 12 h post-cysteamine) resulted in a 69% inhibition of ulceration, and the antacid Maalox (2 ml, administered p.o. at 0, 2, 4, 6 and 12 h post-cysteamine) completely prevented ulceration. The failure of pr-MDI to protect against duodenal ulceration is discussed in relation to its pharmacological mechanism of action and the pathogenetic mechanism of action of cysteamine.     

Effect of l-ornithine l-aspartate against thioacetamide-induced hepatic damage in rats

Objective:

To investigate the hepatoprotective activity of L-ornithine-L-aspartate against thioacetamide (TAA)-induced hepataopathy in rats.

Materials and Methods:

The hepatoprotective activity of L-ornithine-L-aspartate (OA) at a dose of 2 g/kg, p.o. for 10 days was evaluated against TAA (250 mg/kg, i.p. for 2 days) induced hepatopathy in rats. Biochemical parameters such as serum aspartate transaminase, alanine transaminase, alkaline phosphatase, bilirubin and glutathione, thiobarbituric acid reactive substances, and protein in liver tissues were estimated to assess the liver function.

Results:

TAA-induced pathogenic changes in the levels of the above indices were significantly (P < 0.01) reversed by the OA treatment. OA treatment also exhibited significant restoration of the hepatic architecture and lobular structure in histological evaluation of the rat liver sections.

Conclusion:

Ornithine aspartate exhibited significant hepatoprotective activity against TAA-induced hepatic damage in rats.     

注射用雷贝拉唑钠对不同溃疡模型大鼠的影响

目的 比较注射用雷贝拉唑钠对不同溃疡模型大鼠的影响。方法 采用幽门结扎法收集胃液,测定注射用雷贝拉唑钠0.5、1.0、2.0、4.0、8.0 mg/kg对大鼠胃液酸度、胃酸总分泌量的影响。制备吲哚美辛引起的胃溃疡模型、醋酸性胃溃疡、大鼠反流性食管炎以及半胱胺型十二指肠溃疡,模型动物iv给予注射用雷贝拉唑钠后,对溃疡进行评分,计算溃疡抑制情况。结果 ①与模型组比较,注射用雷贝拉唑钠8 mg/kg组胃液分泌量,0.5、4.0、8.0 mg/kg组胃液酸度,2、4、8 mg/kg剂量组胃酸分泌量均显著降低（P<0.05、0.01）。②与模型组比较,0.5、1.0、2.0、4.0 mg/kg剂量组吲哚美辛引起的溃疡得分均显著降低（P<0.05、0.01）。③注射用雷贝拉唑钠1 mg/kg对大鼠醋酸性胃溃疡、反流性食管炎、半胱胺型十二指肠溃疡抑制率分别为18.2%、37.5%和23.4%,其中对反流性食管炎的抑制作用具有显著性差异（P<0.05）。结论 注射用雷贝拉唑钠抑制胃酸分泌,对吲哚美辛引起胃溃疡、反流性食管炎、十二指肠溃疡和醋酸性胃溃疡均有抑制作用。     

Antidepressant-like effect of novel 5-HT3 receptor antagonist N-n-butyl-3-ethoxyquinoxalin-2-carboxamide (6p): An approach using rodent behavioral antidepressant tests

Objective:

The present study was designed to investigate the antidepressant potential of N-n-butyl-3-ethoxyquinoxalin-2-carboxamide (6p), a novel 5-HT₃ receptor antagonist in rodent behavioral models of depression.

Materials and Methods:

The compound 6p was examined in various behavioral models like forced swim test (FST), tail suspension test (TST), mechanistic models [5-hydroxytryptophan (5-HTP)-induced head twitch and reserpine-induced hypothermia (RIH)], and in chronic surgery model-olfactory bulbectomy in rats.

Results:

Compound 6p (1, 2, and 4 mg/kg, i.p.) exhibited antidepressant-like effect in FST and TST after acute treatment without having an effect on baseline locomotor activity. Moreover, 6p (2 mg/kg, i.p.), potentiated the 5-HTP–induced head twitch responses in mice and inhibited the RIH in rats. Chronic treatment (14 days) with 6p (1 and 2 mg/kg, p.o.) and paroxetine (10 mg/kg, p.o.) in rats significantly reversed the behavioral anomalies induced by bilateral olfactory bulbectomy using open field exploration.

Conclusion:

The preliminary studies reveal that compound 6p exhibits antidepressant-like effect in behavioral rodent models of depression.KEY WORDS: 5-HT₃ receptor antagonists, antidepressant, forced swim test, quinoxaline, serotonin     

Antidiabetic activity of aqueous root extract of Ichnocarpus frutescens in streptozotocin-nicotinamide induced type-II diabetes in rats

Objective:

To evaluate the antidiabetic activity of aqueous extract of roots of Ichnocarpus frutescens in streptozotocin-nicotinamide induced type-II diabetes in rats.

Materials and Methods:

Streptozotocin-nicotinamide induced type-II diabetic rats (n = 6) were administered aqueous root extract (250 and 500 mg/kg, p.o.) of Ichnocarpus frutescens or vehicle (gum acacia solution) or standard drug glibenclamide (0.25 mg/kg) for 15 days. Blood samples were collected by retro-orbital puncture and were analyzed for serum glucose on days 0, 5, 10, and 15 by using glucose oxidase-peroxidase reactive strips and a glucometer. For oral glucose tolerance test, glucose (2 g/kg, p.o.) was administered to nondiabetic control rats and the rats treated with glibenclamide (10 mg/kg, p.o.) and aqueous root extract of Ichnocarpus frutescens. The serum glucose levels were analyzed at 0, 30, 60, and 120 min after drug administration. The effect of the extract on the body weight of the diabetic rats was also observed.

Results:

The aqueous root extract of Ichnocarpus frutescens (250 and 500 mg/kg, p.o.) induced significant reduction (P < 0.05) of fasting blood glucose levels in streptozotocin-nicotinamide induced type-II diabetic rats on the 10^th and 15^th days. In the oral glucose tolerance test, the extract increased the glucose tolerance. It also brought about an increase in the body weight of diabetic rats.

Conclusion:

It is concluded that Ichnocarpus frutescens has significant antidiabetic activity as it lowers the fasting blood sugar level in diabetic rats and increases the glucose tolerance.     

Screening of Ficus religiosa leaves fractions for analgesic and anti-inflammatory activities

Objective:

To evaluate the different fractions of dried leaves of Ficus religiosa Linn for analgesic and anti-inflammatory activity using different models of pain and inflammation

Materials and Methods:

The analgesic activity of F. religiosa carried out using acetic acid-induced writhing in mice and tail flick test in rats. The anti-inflammatory activity was evaluated using carrageenan-induced rat paw edema and cotton pellet-granuloma formation in rats. Five different fractions (FRI, FRII, FRIII, FRIV and FRV) of F. religiosa at the dose level of 20 and 40 mg/kg, p.o were tested.

Results:

The fraction FRI (40 mg/kg, p.o.) and FRIII (40 mg/kg, p.o) were found to be more effective (P<0.01) in preventing carrageenan induced rat paw edema, cotton pellet granuloma formation, and acetic acid induced writhing compared to the other fractions. FRI (20 mg/kg, p.o.) and FRIII (20 mg/kg, p.o.) were also found to be more effective in increasing latency period in tail flick method.

Conclusion:

Out of five different fractions of F. religiosa leaves tested, FRI and FRIII possess potent analgesic and anti-inflammatory activities against different models of inflammation and pain.KEY WORDS: Ficus religiosa, granuloma formation, carrageenan, tail flick, acetic acid     

Hepatoprotective activity of petroleum ether, diethyl ether, and methanol extract of Scoparia dulcis L. against CCl4-induced acute liver injury in mice

Objectives:

The present study was aimed at assessing the hepatoprotective activity of 1:1:1 petroleum ether, diethyl ether, and methanol (PDM) extract of Scoparia dulcis L. against carbon tetrachloride-induced acute liver injury in mice.

Materials and Methods:

The PDM extract (50, 200, and 800 mg/kg, p.o.) and standard, silymarin (100 mg/kg, p.o) were tested for their antihepatotoxic activity against CCl4-induced acute liver injury in mice. The hepatoprotective activity was evaluated by measuring aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and total proteins in serum, glycogen, lipid peroxides, superoxide dismutase, and glutathione reductase levels in liver homogenate and by histopathological analysis of the liver tissue. In addition, the extract was also evaluated for its in vitro antioxidant activity using 1, 1-Diphenyl-2-picrylhydrazyl scavenging assay.

Results:

The extract at the dose of 800 mg/kg, p.o., significantly prevented CCl4-induced changes in the serum and liver biochemistry (P < 0.05) and changes in liver histopathology. The above results are comparable to standard, silymarin (100 mg/kg, p.o.). In the in vitro 1, 1-diphenyl-2-picrylhydrazyl scavenging assay, the extract showed good free radical scavenging potential (IC 50 38.9 ± 1.0 μg/ml).

Conclusions:

The results of the study indicate that the PDM extract of Scoparia dulcis L. possesses potential hepatoprotective activity, which may be attributed to its free radical scavenging potential, due to the terpenoid constituents.     

Effects of a new histamine H2-receptor antagonist, ranitidine, on experimental acute gastric and duodenal ulcers (author's transl)

Ranitidine at 100 to 200 mg/kg (i.d. or p.o.) potently inhibited the development of Shay ulcers, indomethacin- or phenylbutazone-induced gastric ulcers and histamine-carbachol-induced duodenal ulcers in rats. Ranitidine at 100 mg/kg (p.o.) also inhibited the development of water-immersion stress-induced gastric ulcers in rats, histamine-induced gastric and duodenal ulcers in guinea pigs, even though the inhibition rate remained within 70%. At that time, the gastric acid output in guinea pigs was reduced with some doses of the drug. Cimetidine at 100 to 200 mg/kg (p.o.) also inhibited the development of indomethacin-, phenylbutazone-, and water-immersion stress-induced gastric ulcers in rats and histamine-induced gastric and duodenal ulcers in guinea pigs. Shay ulcers and histamine-carbachol-induced duodenal ulcers in rats were not affected by cimetidine. Both ranitidine and cimetidine inhibited the gastric acid output in pylorus-ligated rats (7 hr); the maximal inhibition being 79.6% and 50.7% respectively. The mechanism by which ranitidine inhibits various experimental ulcers might be mainly the inhibition of gastric secretion. Gefarnate at 300 mg/kg (p.o.) significantly inhibited phenylbutazone-induced gastric ulcers in rats but had no effect on other ulcer models.     

Evaluation of hepatoprotective activity of Cissus quadrangularis stem extract against isoniazid-induced liver damage in rats

Objective:

The study was designed to investigate the hepatoprotective activity of methanol extract of Cissus quadrangularis (CQ) against isoniazid-induced hepatotoxicity in rats.

Materials and Methods:

The successive petroleum ether (60–80°C) and methanol extracts of C. quadrangularis were used. Hepatic damage was induced in Wistar rats by administering isoniazid (54 mg/kg, p.o.) once daily for 30 days. Simultaneously, CQ (500 mg/kg p.o) was administered 1 h prior to the administration of isoniazid (54 mg/kg, p.o.) once daily for 30 days. Silymarin (50 mg/kg p.o) was used as a reference drug.

Results:

Elevated levels of aspartate transaminase, alanine transaminase, alkaline posphatase, and bilirubin following isoniazid administration were significantly lowered due to pretreatment with CQ. Isoniazid administration significantly increased lipid peroxidation (LPO) and decreased antioxidant activities such as reduced glutathione, superoxide dismutase, and catalase. Pretreatment of rats with CQ significantly decreased LPO and increased the antioxidant activities.

Conclusion:

The results of this study indicated that the hepatoprotective effect of CQ might be attributed to its antioxidant property.