The impact of subchronic lead poisoning on the vascular effect of nitric oxide in rats

In comparison with controls rats given 50 ppm of lead, an increase in maximal response to N-ω-nitro-l-arginine (P < 0.01) and acetylcholine (P < 0.05) and a shift to the left of the dose-response curve for acetylcholine were demonstrated. Vascular responses in rats, who were given 100 ppm of lead, were similar to those observed in the control group. It is concluded that lead induces NO-mediated changes of vascular tone and vascular reactivity only in the small range of doses known as hypertensive.