This study investigates the effects of antinerve growth factor (anti-NGF) application on isolated ileal contractility in the rat. For this purpose, rats were divided into four groups. The control animals (n=8) received only intraperitoneal injection of an isotonic NaCl solution (i.p). Anti-NGF was daily administered intraperitoneally at the dose of 1 ng/g level in the first experimental group (n=8), and at doses of 10 ng/g (n=7) and 40 ng/g (n=7) in the second and third experimental groups, respectively. Seven days after the injections rats were sacrificed and ileum segments were isolated. Responses to acetylcholine (ACh) were evaluated by using standard Tyrode, double-calcium Tyrode and
calcium-free Tyrode solutions. The average peak amplitude of ACh-induced contractions recorded in standard Tyrode solution was significantly decreased in all three experimental groups as compared to the control group (p<0.05). When double-calcium Tyrode solution was used as the perfusion medium, the responses to ACh were also lower in all anti-NGF applied groups as compared to its control group (p<0.05). Our results showed that the application of anti-NGF reduced the contractile responses of the rat isolated ileum apparently by decreasing the calcium influx from the extracellular medium.