Stimulation by nizatidine, a histamine H2-receptor antagonist, of duodenal HCO3- secretion in rats: relation to anti-cholinesterase activity

Figure 5 Effects of nizatidine and acetylcholine, either alone or in combination, on duodenal HCO₃^- secretion in rats. The HCO₃^- secretion was measured by perfusing a duodenal loop with saline and by adding 10 mM HCl to the reservoir. Nizatidine (3 mg/kg) and acetylcholine (0.003 mg/kg), either alone or in combination, were administered i.v. after the basal secretion had well stabilized, and the HCO₃^- secretion was measured for 2 h. Data are expressed as % of basal values and represe nt the means ± SE of values determined every 15 min from 6 rats. Lower panel shows △increase of HCO₃^- output for 2 h. Data are presented as the means ± SE from 6 rats. Significant difference at P < 0.05^a from control; ^bfrom nizatidine or acetylcholine.