Ameliorating effect of melatonin against nicotine induced lung and heart toxicity in rats.

The present study was carried out to investigate the ameliorative effects of melatonin against nicotine-induced heart and lung toxicity. For this purpose, 75 mature male Sprague Dawley (SD) rats weighing 150-170 g were randomly divided into five groups (15 rats each): control group (rats were I/P injected with 1% ethanol in saline), nicotine group (rats were I/P injected with 0.6 mg/kg body weight), and combined nicotine and melatonin groups (rats received nicotine as in the previous group and melatonin at a dose of 1, 5, or 10 mg/kg body weight, respectively); all treatments were continued for 21 days.