N (G)-nitro-L-arginine Methyl Ester Protects Against Hormonal Imbalances Associated with Nicotine Administration in Male Rats.

Abstract

Background:The administration of nicotine is associated with altered hormonal imbalances and increased serum and testicular nitric oxide (NO) level.Aim:This study sought to investigate the effects of NO inhibition with NG-nitro-L-arginine methyl ester (L-NAME) on altered hormonal imbalance in adult male albinorats.Materials and Methods:Rats were administered with 0.5 mg/kg body weight (BW) and 1.0 mg/kg BW nicotine and were treated with L-NAME in the drinking water or drinking water alone for 30 days. Serum was analyzed for testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), and prolactin using radioimmunoassay.Results:Nicotine administration significantly decreased (P < 0.05) testosterone in the low and high dose treated groups and FSH in the high dose treated group when compared with the control group. There was a significant increase (P < 0.05) in mean LH and prolactin level in the high dose treated group when compared with the control. Concomitant treatment with nicotine and L-NAME produced significant increases in testosterone and FSH, and a decrease in prolactin in 1.0 mg/kg BW. L-NAME alone did not lead to a significant increase in testosterone when compared with control.Conclusion:These data demonstrate that the suppressive effects of nicotine on testosterone level of the adult male rat can be prevented by NOS blockade with L-NAME. It appears that these beneficial effects are mediated primarily within the gonad; however, the involvement of the pituitary cannot be totally ruled out.