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

Table 2 Inhibition by nizatidine, famotidine, neostigmine and cisapride of acetylcholinesterase activity in rat erythrocyte and plasma

Drugs	IC50 (M)
	Rat erythrocytes	Plasma
Nizatidine	1.4 × 10-6	5.7 × 10-4
Neostigmine	1.1 × 10-7	3.3 × 10-6
Famotidine	1.0 × 10-3 <	1.0 × 10-3 <
Cisapride	1.0 × 10-3 <	1.0 × 10-3 <

Values represent the IC₅₀ of AChE activity for each drug. The experiments were performed in triplicate against AChE of rat erythrocyte and plasma.