Exacerbation of cold restraint-induced gastric ulcer by GABA in mice
Abstract
AIM: To study the effect of GABA on cold restraint-induced gastric ulcer (CRGU) and its mechanism.
METHODS: CRGU was produced in adult male mice at 1 degree C in cold room under restraint for 1 h. The ulcer index indicated the severity of gastric mucosa lesion. Gastric mucin was determined with alcian blue dye.
RESULTS: GABA 2 mumol (i.c.v.) accelerated CRGU, Bicuculline (Bic) 0.2 mumol (i.c.v.) did not affect CRGU, whereas Baclofen (Bac) 4 mumol (i.c.v.) exacerbated CRGU. Bic did not modify the exacerbation of CRGU by GABA and Bac. Atropine (Atr) 0.2 mg.kg-1 (s.c.) and Phentolamine (Phen) 2.5 mg.kg-1 inhibited CRGU, and abolished the exacerbation of CRGU by GABA. Cold restraint (CR) decreased the amount of the gastric mucin, but GABA 2 mumol had no effect on CR gastric mucin.
CONCLUSION: While GABA-B receptor in brain was activated, exogenous GABA exacerbated CRGU via vagal and sympathetic nerves, bearing no relation to decrease of the gastric mucin or weakening of the gastric mucosal barrier.
Keywords:
METHODS: CRGU was produced in adult male mice at 1 degree C in cold room under restraint for 1 h. The ulcer index indicated the severity of gastric mucosa lesion. Gastric mucin was determined with alcian blue dye.
RESULTS: GABA 2 mumol (i.c.v.) accelerated CRGU, Bicuculline (Bic) 0.2 mumol (i.c.v.) did not affect CRGU, whereas Baclofen (Bac) 4 mumol (i.c.v.) exacerbated CRGU. Bic did not modify the exacerbation of CRGU by GABA and Bac. Atropine (Atr) 0.2 mg.kg-1 (s.c.) and Phentolamine (Phen) 2.5 mg.kg-1 inhibited CRGU, and abolished the exacerbation of CRGU by GABA. Cold restraint (CR) decreased the amount of the gastric mucin, but GABA 2 mumol had no effect on CR gastric mucin.
CONCLUSION: While GABA-B receptor in brain was activated, exogenous GABA exacerbated CRGU via vagal and sympathetic nerves, bearing no relation to decrease of the gastric mucin or weakening of the gastric mucosal barrier.