Glavin G B
Department of Pharmacology, Faculty of Medicine, University of Manitoba, Winnipeg, Canada.
Life Sci. 1994;55(24):PL451-4. doi: 10.1016/0024-3205(94)00531-1.
A variety of dopaminergic compounds influence gastric secretion and response to injury. In particular, agonists of the D1 receptor are gastroprotective when given either centrally of peripherally. In the present studies, we show that an indirect dopamine (DA) promoter, GBR 12909, a selective DA uptake inhibitor given ip but not icv, protects against restraint-cold stress-induced gastric mucosal injury. This protection likely occurred through preservation of gastric adherent mucus, since all doses of GBR 12909 resulted in gastric mucus levels at or near control (non-stressed) values. When given, ip, GBR 12909 did not influence basal gastric acid secretion in conscious rats, however, when given icv, GBR 12909 inhibited gastric acid secretion with an ED50 of about 0.5 microgram (1.13 umoles). We conclude that both central and peripheral DA contributes to gastrointestinal integrity through reduction of aggressive elements in the gut as well as by enhancing gastric mucosal defence.
多种多巴胺能化合物会影响胃分泌及对损伤的反应。特别是，D1受体激动剂无论是经中枢还是外周给药都具有胃保护作用。在本研究中，我们发现一种间接多巴胺（DA）促进剂GBR 12909，一种腹腔注射而非脑室内注射的选择性DA摄取抑制剂，可预防束缚-冷应激诱导的胃黏膜损伤。这种保护作用可能是通过保留胃黏附黏液实现的，因为所有剂量的GBR 12909都会使胃黏液水平达到或接近对照（非应激）值。腹腔注射GBR 12909时，对清醒大鼠的基础胃酸分泌没有影响，然而，脑室内注射GBR 12909时，会抑制胃酸分泌，半数有效剂量（ED50）约为0.5微克（1.13微摩尔）。我们得出结论，中枢和外周多巴胺均通过减少肠道中的攻击因子以及增强胃黏膜防御来维持胃肠道完整性。
