Antiulcer activity of cod liver oil in rats

Objective:

Cod liver oil is used widely as a dietary supplement. The present study was carried out to evaluate the effect of cod liver oil (0.5 g/kg, p.o. and 1 g/kg, p.o.) on gastric and duodenal ulcers.

Materials and Methods:

The study was carried out on different gastric ulcer models such as acetic acid induced chronic gastric ulcers, pylorus ligation, indomethacin induced ulcers, stress induced ulcers and ethanol induced ulcers. The duodenal ulcers were induced using cysteamine hydrochloride (HCl). Ranitidine (50 mg/kg p.o.) and misoprostol (100 µg/kg, p.o.) were used as standard drugs.

Results:

Both doses of cod liver oil showed gastric ulcer healing effect in acetic acid induced chronic gastric ulcers, produced gastric antisecretory effect in pylorus-ligated rats and also showed gastric cytoprotective effect in ethanol-induced and indomethacin-induced ulcer. Cod liver oil also produced a significant reduction in the development of stress induced gastric ulcers and cysteamine induced duodenal ulcer. The high dose of cod liver oil (1 g/kg, p.o.) was more effective compared to the low dose (0.5 g/kg, p.o.).

Conclusion:

Cod liver oil increases healing of gastric ulcers and prevents the development of experimentally induced gastric and duodenal ulcers in rats.     

Possible biochemical effects following inhibition of ethanol-induced gastric mucosa damage by Gymnema sylvestre in male Wistar albino rats

Context: Gymnema sylvestre (GS) R. Br. (Gymnema) (Asclepiadaceae) has been used from ancient times as a folk medicine for the treatment of diabetes, obesity, urinary disorder, and stomach stimulation.

Objective: The present study was designed to investigate the effects of G. sylvestre leaves ethanol extract on gastric mucosal injury in rats.

Materials and methods: Gastric mucosal damage was induced by 80% ethanol in 36?h fasted rats. The effect of G. sylvestre on gastric secretions induced in Shay rats was estimated. In stomach, wall mucus, non-protein sulfhydryl groups (NP-SH), malondialdehyde (MDA), total proteins and nucleic acids levels were estimated. Histopathological changes were observed.

Results: G. sylvestre pretreatment at doses of 100, 200 and 400?mg/kg provided 27, 49, and 63% protection against the ulcerogenic effect of ethanol, respectively. Pylorus ligation accumulated 10.24?mL gastric secretions with 66.56 mEq of acidity in control rats. Pretreatment with G. sylvestre significantly inhibited the secretions volume and acidity in dose-dependent manner. Ethanol caused significant depletion in stomach-wall mucus (p < 0.001), total proteins (p < 0.01), nucleic acids (p < 0.001), and NP-SH (p < 0.001) levels. Pretreatment with G. sylvestre showed protection against these depleted levels in dose-dependent manner. The MDA levels increased from 19.02 to 29.22 nmol/g by ethanol ingestion and decreased with G. sylvestre pretreatments in dose-dependent manner.

Conclusion: The protective effect of G. sylvestre observed in the present study is attributed to its effect on mucus production, increase in nucleic acid and NP-SH levels, which appears to be mediated through its free radical scavenging ability and/or possible cytoprotective properties.     

网脉橐吾醇提物抗大鼠实验性胃溃疡作用研究

目的:研究网脉橐吾醇提物抗大鼠实验性胃溃疡的作用。方法:采用无水乙醇、幽门结扎、吲哚美辛和醋酸性大鼠胃溃疡模型,通过测定溃疡指数,评价网脉橐吾醇提物对大鼠胃溃疡的影响;通过测定溃疡大鼠胃酸分泌量、pH值、胃液总酸度和胃蛋白酶活性,初步探讨其可能的作用机制。结果:与模型组比较,网脉橐吾醇提物可明显降低无水乙醇、幽门结扎和吲哚美辛所致的大鼠溃疡指数(P<0.05),但对醋酸所致大鼠胃溃疡无明显治疗作用(P>0.05);同时,其对大鼠胃液分泌量、pH值、总酸度、胃蛋白酶活性均无明显影响(P>0.05)。结论:网脉橐吾醇提物对无水乙醇、幽门结扎和吲哚美辛所致大鼠胃溃疡具有明显的保护作用,但对醋酸所致大鼠胃溃疡的治疗作用较弱,其胃黏膜保护作用的机制有待于进一步研究。     

Suppression by protease-activated receptor-2 activation of gastric acid secretion in rats

Activation of protease-activated receptor-2 (PAR-2), a receptor activated by trypsin/tryptase, induces neurally mediated gastric mucus secretion accompanied by mucosal cytoprotection. In the present study, we investigated whether PAR-2 could modulate gastric acid secretion in rats. Messenger RNAs for PAR-2 and PAR-1 were detected in the gastric mucosa and smooth muscle. The PAR-2-activating peptide SLIGRL-NH(2), but not the inactive control peptide, when administered i.v., strongly suppressed gastric acid secretion in response to carbachol, pentagastrin or 2-deoxy-D-glucose in the rats with a pylorus ligation. The PAR-2-mediated suppression of acid secretion was resistant to cyclooxygenase inhibition or ablation of sensory neurons by capsaicin. Our results provide novel evidence that in addition to stimulating neurally mediated mucus secretion, activation of PAR-2 suppresses gastric acid secretion independently of prostanoid production or sensory neurons. These dual actions of PAR-2 would result in gastric mucosal cytoprotection.     

Effects of cimetidine and atropine sulfate on gastric secretion and healing of gastric and duodenal ulcers in rats.

Cimetidine, a new histamine H2-receptor antagonist (50 or 100 mg/kg) and atropine sulfate (15 mg/kg) given intraduodenally, markedly inhibited gastric secretion in pylorus-ligated rats. Cimetidine (100 or 200 mg/kg/day) given for 10 or 12 consecutive days orally in two divided doses, significantly promoted the healing rate of both gastric and duodenal ulcers induced in rats. Atropine (30 mg/kg/day) also significantly accelerated the healing of duodenal ulcers but failed to affect gastric ulcers.     

小牛血去蛋白提取物对大鼠实验性胃溃疡的疗效观察

目的　探讨小牛血去蛋白提取物 (DCBE)对大鼠实验性胃溃疡的治疗作用。方法　乙酸诱导的SD大鼠溃疡模型 ,随机分为 3组。第 1组为对照组 ,生理盐水灌胃 ;第 2、3组DCBE(30、60mg·kg- 1 )灌胃。实验的第 2、4周测量胃酸度、胃蛋白酶活性、溃疡面积、组织白细胞数、髓过氧化物酶(myeloperoxidase,MPO)活性。 结果　DCBE能缩小乙酸诱导大鼠胃溃疡的溃疡面积 ,该作用与降低组织的MPO活性、减少白细胞数等相关 ,但不影响胃酸及胃蛋白酶的活性。结论　DCBE能促进乙酸诱导大鼠胃溃疡的组织愈合     

Organoprotection and cytoprotection of histamine differ in rats

Aims  The aim of the present study was to compare the organoprotective (in vivo) and cytoprotective (in vitro) effects of histamine. Methods  In vivo, gastric mucosal damage was produced by intragastric (ig) administration of 1 ml 96% ethanol (EtOH) in Sprague-Dawley rats. The animals were sacrificed 1 h after EtOH administration, when the gastric mucosal damage was measured. Histamine was given subcutaneously (sc) 30 min before administration of EtOH with and without PGI₂Na (5 μg/kg sc). Gastric acid secretion was also measured 1 h after pylorus ligation in control (saline-), histamine- and PGI₂-treated animals. The affinity, intrinsic activity curves and the values of pD₂ and pA₂ were determined in EtOH-treated and in PGI₂-treated animals. For the in-vitro studies, a mixed population of rat gastric mucosal cells was isolated by pronase digestion. Cells were preincubated for 60 min with histamine (10^♪−8-10⁻⁶ mol/L) with or without PGI₂Na (10⁻⁴ mol/L). At the end of this incubation period, cells were treated with 15% EtOH with or without 10⁻⁶-10³ mol/L indomethacin (IND) for 5 min. Cell viability was tested by trypan blue exclusion test and succinic dehydrogenase activity. Results  

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.     

艾普拉唑钠对大鼠胃溃疡模型的影响

目的:研究注射用艾普拉唑钠对幽门结扎和束水应激大鼠胃溃疡模型的治疗作用。方法:100只健康SD大鼠,随机分为模型对照组、艾普拉唑钠低、中、高剂量组(0.3,0.9和2.7 mg·kg^-1)和艾普拉唑片组(0.9 mg·kg^-1)。各给药组单次给予相应药液,模型对照组给予等量的溶剂。采用幽门结扎和束水应激法建立2种大鼠胃溃疡模型。通过测定胃酸总分泌量、胃液pH、胃蛋白酶活力、前胃和腺胃溃疡面积等指标以及组织病理学检查,与艾普拉唑肠溶片比较,探讨注射用艾普拉唑钠的药效作用。结果:艾普拉唑钠0.9和2.7 mg·kg^-1组胃液pH升高,胃溃疡面积、胃酸总分泌量、胃蛋白酶活力降低,各剂量组胃黏膜组织病理病变程度减轻,与模型对照组比差异具有统计学意义(P<0.05或P<0.01)。结论:艾普拉唑钠通过抑制胃酸分泌,对大鼠急性胃损伤具有治疗作用。     

Gastric antiulcer,antisecretory and cytoprotective properties of celery (Apium graveolens) in rats

In the present investigation, an ethanol extract of celery [Apium graveolens L. (Apiaceae/Umbelliferae)], at doses of 250 and 500?mg/kg body weight, was evaluated for antigastric ulcer activity using various experimental gastric ulcer models in rats. Ulcers were induced by indomethacin, cytodestructive agents (80% ethanol, 0.2?M NaOH and 25% NaCl) and cold restraint stress. Gastric secretory studies were undertaken by using pylorus ligation (Shay rat model). In addition to gastric wall mucus (GWM), non-protein sulfhydryl (NP-SH) and malondialdehyde (MDA) were also estimated in gastric tissues after 80% ethanol treatment. Pretreatment of celery extract produced dose-dependent reduction in all experimentally induced gastric lesions. Ethanol (80%) decreased the levels of GWM, NP-SH and increase in MDA concentration in gastric tissue. Celery extract showed the ability to significantly replenish the ethanol-induced depleted levels of GWM and gastric mucosal NP-SH. The gastric mucosal MDA level was also significantly lowered in extract pretreated rats. The celery extract showed stomach protection against the models used for ulcerogenesis. Results were further confirmed by using histopathological assessment. The phytochemical screening showed the presence of various chemical constituents such as flavonoids, tannins, volatile oils, alkaloids, sterols and/or triterpenes. Acute toxicity test revealed no deleterious or toxic symptoms or mortality over a period of 14 days. However, the LD₅₀ was found to be 7.55?g/kg, and showed a large margin of safety. The results suggest that Apium graveolens extract significantly protects the gastric mucosa and suppresses the basal gastric secretion in rats, possibly through its antioxidant potential.     

Effect of acid secretion blockade on acute gastric mucosal lesions induced by Tityus serrulatus scorpion toxin in anaesthetized rats

Scorpion venom (TX) promotes gastric acid and pepsin secretion leading to acute gastric mucosal lesions (AGML), when injected in animals.The goal of the present study was to observe the effects of acid gastric secretion blockers over the incidence of TX-induced AGML in vivo. To verify this model, we used male albino rats, fasted 18-20 h (n=122) and anaesthetized with urethane (1.4 g/kg, i.p.). Their trachea and left femoral vein were both cannulated; the first to avoid airway obstructions during scorpion intoxication and the second for administration of saline, TX and acid blockers. Following the surgical procedure, the animals were divided in 10 groups of at least 10 animals each. Control groups were injected with NaCl 0.9% 1 ml/kg (n=10) or TX 375 μg/kg (n=32). Test groups (n=10, each) received atropine 5 mg/kg, cimetidine 10 mg/kg, ranitidine 2.5 mg/kg, ranitidine 5 mg/kg, omeprazol 1 mg/kg, omeprazol 4 mg/kg, octreotide 80 and octreotide 100 μg/kg 10 min before the TX was injected. After 1 h of intoxication, the stomach was resected for macroscopic study and the gastric secretion was collected for volume, pH and acid output assessment. We observed that all blockers were able to completely or partially prevent the TX-induced acid secretion as well as the AGML (p<0.05). Our data suggest the TX-induced AGML can be prevented by different class of acid blockers injected before the intoxication.     

Inhibition of leukotriene B4 formation in rat peritoneal neutrophils by an ethanolic extract of the gum resin exudate of Boswellia serrata.

Suspensions of rat peritoneal polymorphonuclear leukocytes (PMNL) elicited with glycogen were stimulated by calcium and ionophore to produce leukotrienes and 5-HETE from endogenous arachidonic acid (AA). We investigated the effect of ethanolic extracts of the gum resin exudate of Boswellia serrata. A concentration-dependent inhibition of LTB4 and 5-HETE production by different charges of exudate extracts were found. All products of the 5-lipoxygenase (5-LOx) from endogenous arachidonic acid (AA) in PMNL were reduced to the same extent by the extracts tested. The ethanolic extract of the gum resin also decreased 5-LOx mediated metabolisation of exogenously added AA to LTB4 and 5-HETE. Since steroidal-type anti-inflammatory drugs do not exert an immediate effect in the test system used, we conclude that the activity of the 5-LOx itself represents the side of inhibition by the gum resin extract. Therefore, an inhibition of 5-LOx catalysed mediator synthesis might be involved in the previously reported anti-inflammatory activity in vivo.     

鳕鱼皮胶原蛋白肽的抗酒精性胃溃疡作用

目的探究鳕鱼皮胶原蛋白及其酶解梯级多肽的抗酒精性胃溃疡作用。方法从鳕鱼皮中提取胶原蛋白并酶解成不同分子量段的胶原肽,采用酒精诱导大鼠急性胃溃疡模型,试验组灌胃给予不同剂量的胶原肽,检测胃溃疡指数、胃溃疡抑制率并对胃溃疡病灶部位进行组织学观察。结果与模型组相比,各受试物均能够降低大鼠胃腺的出血损伤。低分子量胶原肽与高分子量胶原肽都能显著降低胃溃疡指数,胃溃疡抑制率分别为46.98%和46.46%(P<0.05);高剂量的胶原蛋白与中分子量胶原肽能极显著降低胃溃疡指数,胃溃疡抑制率分别为57.16%和65.16%(P<0.01)。结论鱼皮胶原蛋白及其酶解梯级多肽能够明显降低大鼠胃溃疡出血和溃疡指数,具有良好的抗酒精性胃溃疡作用。     

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.     

PTICE预防幽门结扎大鼠胃溃疡及其作用机制

目的研究河纯Ⅰ型胶原蛋白提取物（PTCE）对幽门结扎模型大鼠胃溃疡的影响，探讨其抗溃疡初步作用机制。方法Shay法制备幽门结扎大鼠胃溃疡模型；滴定法测定胃液游离酸和总酸；阿尔新蓝法测定胃黏液糖蛋白含量；放免法测定血清胃泌素含量。结果PT／CE灌胃0．3、0．6或1．2g／kg4d可显著抑制幽门结扎大鼠胃溃疡发生、抑制胃液、胃液游离酸和总酸分泌，显著降低血清胃泌素水平，和显著升高胃黏膜黏液糖蛋白含量，与幽门结扎病理组比较有显著统计学意义（P〈0．01或P〈0．05）。结论 PTICE抗消化性溃疡和胃黏膜保护作用，与其抑制胃泌素和胃酸分泌，促进胃黏膜黏液糖蛋白分泌或生成有关。     

In vivo anti-ulcerogenic effect of okra (Abelmoschus esculentus) on ethanol-induced acute gastric mucosal lesions

Context: Okra, Abelmoschus esculentus (L.) (Malvaceae), is a medicinal plant widely used in Turkish traditional medicine for the treatment of various diseases such as ulcers and gastritis.

Objective: In the present study, we evaluated the gastroprotective effect of okra against ethanol-induced acute gastric mucosal injury in animal models.

Materials and methods: Wistar rats were treated with 500, 250 or 100?mg/kg okra; 20?mg/kg famotidine (Fam); and 75?mg/kg quercetin (Que). Following a 60?min period, all the rats were given 1?mL of ethanol (80%). One hour after the administration of ethanol, all groups were sacrificed.

Results: At 5000?mg/kg, the extract produced (okra) no signs of toxicity in animals. Okra 500, 250, 100, Fam 20 and Que 75 inhibited ulcer formation by 81.0, 67.5, 67.0, 76.3 and 72.4%, respectively. Okra 500 significantly decreased edema, hemorrhage and inflammation scores compared with the ethanol group (p?p?p?p?Discussion and conclusions: Our in vivo data indicate that okra has a gastroprotective effect against ethanol and could reduce the gastric ulcer as seen from biochemical and histopathological results. We suggest that okra could be a possible therapeutic antiulcer agent.     

胃灵冲剂对大鼠乙酸胃溃疡愈合质量的影响

目的 研究胃灵冲剂对大鼠胃溃疡愈合质量的影响.方法 用冰醋酸制备大鼠慢性胃溃疡模型,随机分为5组,分别灌胃胃灵冲剂(2.4、4.8、9.6g·kg-1)、雷尼替丁、生理盐水.用阿利斯蓝染液对胃壁结合粘液进行测定;注墨汁法测量溃疡体积.结果 胃灵冲剂各剂量组的胃壁结合粘液量高于生理盐水组;胃灵冲剂(4.8、9.6g·kg-1)组的溃疡面积明显小于生理盐水对照组.结论 胃灵冲剂能促进冰醋酸胃溃疡愈合.     

Mechanism for gastric antisecretory effects of desmethylimipramine in rats

The mechanism for the gastric antisecretory action of desmethylimipramine (DMI) was studied using the pylorus-ligated rat preparation. DMI was approximately 40 times more potent in decreasing gastric acid secretion when given into the lateral ventricles of the brain than when administered intravenously. The antisecretory effects of DMI could be blocked by the α₂-adrenoceptor antagonists yohimbine and SK&F 72223 and mimicked by central administration of an α₂-agonist. It could not be blocked by the α₁-antagonist prazosin or mimicked by α₁-adrenoceptor agonists. SK&F 72223 and yohimbine themselves produced small increases in gastric acid, but the increase in acid output by SK&F 72223 failed to reduce the antisecretory response to atropine. Since DMI is not an α₂-adrenoceptor agonist, but is a potent inhibitor of norepinephrine uptake, these data suggest that the effects of DMI on gastric acid secretion are mediated indirectly via inhibition of catecholamine uptake at central synapses containing α₂-adrenoceptors.     

吲哚美辛对大鼠胃功能的影响及作用机制研究

目的 研究吲哚美辛对大鼠胃酸分泌及胃蛋白酶活力的影响及其作用机制。 方法 大鼠分为对照组和吲哚美辛低、中、高剂量组。测定各组大鼠胃酸分泌量及胃蛋白酶活力,测定血清胃泌素含量。 结果 吲哚美辛可显著增加胃酸分泌量、增加胃酸分泌速度及增加胃蛋白酶活力,促进胃泌素分泌。 结论 吲哚美辛可显著促进胃酸分泌,增加胃蛋白酶活力,这与其促进胃秘素分泌有关。     

参积护胃颗粒对无水乙醇诱导大鼠实验性胃溃疡的保护作用研究

目的观察参积护胃颗粒对无水乙醇诱导大鼠实验性胃溃疡的保护作用,为临床应用参积护胃颗粒治疗胃溃疡提供实验依据。方法 60只SD大鼠按体重、性别随机分为正常组,模型组,胃康灵胶囊组,参积护胃颗粒低、中、高剂量组共6组。参积护胃颗粒低、中、高剂量组分别按生药2.61、5.22、10.44 g·kg^-1灌胃,胃康灵胶囊组按0.5 g·kg^-1灌胃,正常组、模型组灌胃等体积蒸馏水,各组灌胃7 d。末次给药1 h后,除正常组外,其他各组均采用无水乙醇灌胃致大鼠急性胃溃疡模型,比较各组溃疡指数及溃疡抑制率,并进行病理组织学检查。结果与模型组比较,胃康灵胶囊组及参积护胃颗粒低、中、高剂量组溃疡指数显著低于模型组（P〈0.01）,从胃黏膜形态及病理组织学观察,胃康灵胶囊组及参积护胃颗粒低、中、高剂量组较模型组黏膜各层破坏显著减轻。结论参积护胃颗粒对无水乙醇致大鼠实验性胃溃疡具有确切的保护作用。