Effects of GABAergic drugs on ethanol-induced gastric lesions.

Different classes of GABAergic drugs--baclofen, GABA, muscimol, Na-valproate, Mg-valproate and diazepam--were tested per os on ethanol-induced gastric lesions in rats. The GABAB agonist baclofen failed to affect gastric susceptibility to ethanol damage, while all the other compounds exerted a dose-dependent inhibition on haemorrhagic-necrotic lesions. This effect was not significantly reversed by the specific GABAA antagonist bicuculline, suggesting it to be independent from GABAA receptors. The blockade of prostaglandin synthesis by indomethacin significantly decreased the gastroprotective action of GABA, Na- and Mg-valproate, but did not antagonize the effect of muscimol and diazepam. Gastric juice volume and pH showed remarkable differences between the various treatments.