Dissociated effect of nicotine on pentagastrin-stimulated acid secretion and blood flow in the rat stomach.

BACKGROUND

Knowledge of the effect of parenteral nicotine on physiologic gastric hyperemia is limited. This study examined the effect of intravenous nicotine on gastric hyperemia and and secretion induced by pentagastrin.

METHODS

In starved, urethane-anesthetized rats, gastric corpus blood flow was monitored continuously in a localized area of the mucosa, using laser Doppler flowmetry. The tip of the laser Doppler flow probe was positioned against the mid-gastric corpus mucosa along the greater curvature. Intravenous nicotine (4 or 40 micrograms/kg/min) or vehicle was infused.

RESULTS

The gastric acid secretion stimulated by intravenous pentagastrin, 20 micrograms/kg/min, was completely inhibited by both doses of nicotine. In contrast to previous reports based on the clearance of weak bases for gastric mucosal blood flow measurement, neither dose of nicotine altered the hyperemia induced by pentagastrin.

CONCLUSION

A dissociated effect of intravenous nicotine on pentagastrin-stimulated gastric acid secretion and hyperemia is documented.