NITRIC-OXIDE DONORS PREFERENTIALLY INHIBIT NEURONALLY MEDIATED RAT GASTRIC-ACID SECRETION

Continuous i.v. infusion of the nitric oxide (NO) donors, S-nitroso-gl utathione (10-50 mu g kg(-1) min(-1)) and S-nitroso-N-acetyl-penicilla mine (10 mu g kg(-1) min(-1)) inhibited neuronally mediated gastric ac id secretion, as induced by gastric distension (20 cm water) or i.v. b olus administration of 2-deoxy-D-glucose (150 mg kg(-1)) in the anaest hetized rat. By contrast, gastric acid responses to i.v. infusion of s ubmaximal doses of pentagastrin (8 mu g kg(-1) h(-1)) or histamine (1 mg kg(-1) h(-1)) were not influenced by these NO donors. These finding s suggest that NO does not directly influence acid secretion in vivo b ut could play an inhibitory modulator role in neuronally mediated acid responses.