Figure 4. Nicotinic receptor inhibition reduces ethanol-induced increases in duodenal bicarbonate secretion.

A). The effects of luminal perfusion of the duodenum with 15% ethanol pretreated with hexamethonium administered as an i.v. bolus dose of 10 mg·kg?¹ followed by a continuous i.v. infusion of 10 mg·kg?¹·h?¹ throughout the experiment. Hexamethonium significantly reduced the bicarbonate secretory response to ethanol. However, during the ethanol exposure in this group, duodenal bicarbonate secretion was significantly increased compared with the preceding basal period. B). The hexamethonium treatment significantly decreased the net fluid flux. In response to luminal ethanol, the net fluid flux was not significantly different from that of the controls. The values are the mean ± SEM; 15% ethanol (n = 11), hexamethonium alone (n = 4), and 15% ethanol + hexamethonium (n = 9). * indicates a significant (p<0.05) increase compared with baseline in the same group, # indicates a significant decrease compared with baseline in the same group and § indicates a significantly lower value compared with the corresponding time point in the ethanol 15% group of animals.