Effect of nicotine and caffeine pretreatment on the gastric mucosal damage induced by aspirin, phenylbutazone, and reserpine in rats.

The effect of nicotine and caffeine pretreatment by feeding nicotine (2.5 mg %), caffeine (30 mg % base), and their combination (nicotine 2.5 mg % + caffeine 30 mg %) in drinking water ad libitum for 21 days was studied on the gastric mucosal damage induced by aspirin, phenylbutazone, and reserpine in rats. When given alone, neither nicotine nor caffeine produced any visibly discernible gastric lesions. Their concurrent administration too, did not produce any gastric mucosal injury. Pretreatment with nicotine, caffeine, and their combination resulted in significant augmentation of gastric ulcers produced by aspirin, phenylbutazone, and reserpine. However, caffeine administration produced a comparatively less profound augmentation of experimentally induced gastric lesions than that produced by nicotine pretreatment. The enhancement of gastric ulcers in the groups pretreated with the combination of nicotine and caffeine followed by one of the drugs was significantly greater than in the groups treated by either of them alone. The effect of nicotine on the mucus neck cell population of the gastric mucosa and on pancreatic bicarbonate secretion and the gastric secretory effect of caffeine may be responsible for the potentiation of the ulcerogenic effects of aspirin, phenylbutazone, and reserpine.