Sharma M, Rai K, Sharma S S, Gupta Y K
Department of Pharmacology, All India Institute of Medical Sciences, New Delhi, India.
Pharmacology. 2000 Feb;60(2):90-6. doi: 10.1159/000028352.
The effect of a free radical generator pyrogallol on gastric emptying was studied in rats. Pyrogallol at doses of 25, 50, 100 and 150 mg/kg (i.p.) produced dose-dependent inhibition of gastric emptying. Pretreatment with vitamin C (100 and 500 mg/kg, p.o.), and vitamin E (100 and 500 mg/kg, p.o.) significantly reversed the inhibition in gastric emptying caused by pyrogallol 100 mg/kg. However, the combination of vitamin C and vitamin E (100 mg/kg) produced synergistic effect. Glutathione (100 mg/kg i.v.) 5-min pretreatment also reversed the inhibition of gastric emptying caused by pyrogallol 100 mg/kg. Ondansetron (3 mg/kg, p.o.) significantly reversed the pyrogallol effect. The effect of pyrogallol on malondialdehyde (MDA) levels and 5-HT levels in the stomach tissue was also studied. Pyrogallol at a dose of 100 mg/kg, i.p., significantly increased MDA levels and 5-HT levels in the stomach. Pretreatment with a combination of vitamin C and vitamin E (100 mg/kg, p.o.) and glutathione (100 mg/kg, i.v.) significantly ameliorated the rise in stomach tissue MDA caused by pyrogallol but had no significant effect on the rise in 5-HT levels caused by pyrogallol. The effect of different doses of 5-HT on gastric emptying was also studied. 5-HT had a differential effect on gastric emptying. The low and high doses (0.1, 0.3 and 30 mg/kg, i.p.) significantly inhibited the gastric emptying while doses ranging from 1 to 10 mg/kg, i.p., had no significant effect on the gastric emptying. The pretreatment with antioxidants, combination of vitamin C and vitamin E (100 mg/kg each, p.o.) and glutathione (100 mg/kg, i. v.) had no effect on the 5-HT (0.3 mg/kg, i.p.)-induced delay in gastric emptying. The result indicate the role of free radicals gastric emptying, and antioxidants may be of potential therapeutic value in disease conditions where free radicals are known to be released and the gastrointestinal effects are observed as symptoms or side effects of drug therapy.
在大鼠中研究了自由基生成剂连苯三酚对胃排空的影响。腹腔注射剂量为25、50、100和150mg/kg的连苯三酚可产生剂量依赖性的胃排空抑制作用。口服维生素C（100和500mg/kg）和维生素E（100和500mg/kg）预处理可显著逆转100mg/kg连苯三酚引起的胃排空抑制。然而，维生素C和维生素E（100mg/kg）联合使用产生了协同作用。静脉注射100mg/kg谷胱甘肽5分钟预处理也可逆转100mg/kg连苯三酚引起的胃排空抑制。昂丹司琼（3mg/kg，口服）可显著逆转连苯三酚的作用。还研究了连苯三酚对胃组织中丙二醛（MDA）水平和5-羟色胺（5-HT）水平的影响。腹腔注射100mg/kg连苯三酚可显著提高胃组织中的MDA水平和5-HT水平。维生素C和维生素E（100mg/kg，口服）及谷胱甘肽（100mg/kg，静脉注射）联合预处理可显著改善连苯三酚引起的胃组织MDA升高，但对连苯三酚引起的5-HT水平升高无显著影响。还研究了不同剂量的5-HT对胃排空的影响。5-HT对胃排空有不同的作用。低剂量和高剂量（0.1、0.3和30mg/kg，腹腔注射）可显著抑制胃排空，而腹腔注射剂量为1至10mg/kg时对胃排空无显著影响。抗氧化剂、维生素C和维生素E联合使用（各100mg/kg，口服）及谷胱甘肽（100mg/kg，静脉注射）预处理对5-HT（0.3mg/kg，腹腔注射）引起的胃排空延迟无影响。结果表明自由基在胃排空中的作用，抗氧化剂在已知有自由基释放且胃肠道效应表现为疾病症状或药物治疗副作用的疾病状态下可能具有潜在的治疗价值。
