EXACERBATION OF COLD RESTRAINT-INDUCED GASTRIC-ULCER BY GABA IN MICE

AIM: To study the effect of GABA on cold restraint-induced gastric ulc er (CRGU) and its mechanism. METHODS: CRGU was produced in adult male mice at 1 degrees C in cold room under restraint for 1 h. The ulcer in dex indicated the severity of gastric mucosa Gastric mucin was lesion. determined with alcian blue dye. RESULTS: GABA 2 mu mol (icy) acceler ated CRGU, Bicuculline (Bic) 0.2 mu mol (icy) did not affect CRGU, whe reas Baclofen (Bac) 4 mu mol (icy) exacerbated CRGU. Bic did not modif y the exacerbation of CRGU by GABA and Bac. Atropine (Atr) 0.2 mg . kg (-1) (sc) and Phentolamine (Phen) 2.5 mg . kg(-1) inhibited CRGU, and abolished the exacerbation of CRGU by GABA. Cold restraint (CR) decrea sed the amount of the gastric mucin, but GABA 2 mu mol had no effect o n CR gastric mucin. CONCLUSION: While GABA-B receptor in brain was act ivated, exogenous GABA exacerbated CRGU via vagal and sympathetic nerv es, bearing no relation to decrease of the gastric mucin or weakening of the gastric mucosal barrier.