The Effects of Nitric Oxide on Volume, Weight and Histology of Pregnant, S Rat Heart

Backgrounds: Nitric oxide (NO) as a lipophilic small molecule is produced from L- Arginine by a family of Nitric oxide Synthase (NOS) enzymes in living organisms. Objective: NO is now recognized as an important signaling molecule involved in a wide range of physiological and pathophysiological processes including cell growth, apoptosis and immunological regulation. The aim of this study is investigation of Nitric oxide effects on Volume, Weight and Histology of Pregnant, s rat Heart. Material &Methods: Forty female Wister rats, weighing 200- 250 gr with a mean age of 8 weeks, were divided into 5 groups (n=8) after making sure that the experimental rats were pregnant. The first group was received 2mg/kg normal saline and the others were received respectively 200mg/kg L-Arginine, 20mg/kg L-NAME and a mixture of the same doses of L-Arginine & L-NAME on 3, 4 and 5th gestational days via intraperitoneal. The control group was not received any injection. Hearts were removed on 18th gestational days, then after weight and volume measuring and tissue preparation via staining by routine H&E methods studied by Light microscopy. Results: Despite the increasing in weight and volume of the L-NAME group, there were no significant differences between groups but most histological changes in L-NAME group were observed. Conclusion: We found that L-NAME in pregnancy can cause histopathological changes in heart tissue via decreasing levels of NO