Effects of L-NAME on morphometric parameters of stomach parietal cells in pregnant rats

Considering nitric oxide (NO) has an important role in many biologic processes of cells and tissues such as in the digestive system and in this system act as a second messenger in pathological and physiological events in gastrointestinal region، in this study we investigated the effects of L-NG-Nitro arginine Methyl Ester (L-NAME) as the NO formation inhibitor on parietal cells of stomach in pregnant rats. Twenty four female rats were prepared and with eight weeks old and 200-250 g weight were used in this study. After matting of the female rats with the male rats، time of observing vaginal plaque considered as the zero day of pregnancy. Then the animals were divided into three groups of studying. Each group was containing eight rats. In this study، except the control group، the saline group received 2 ml/kg normal saline and experimental group received 20 ml/kg L-NAME interaperitoneally (IP)، respectively on third، fourth، and fifth days of pregnancy for evaluation of its effects. On the 18th day of pregnancy، after anesthesia with ether، the animals were killed and dissected and the laparotomy was performed to separate the mother’s stomach. Then، the stomach was fixed in 10% formalin and after tissue passage، the sections were stained with Hematoxylin-Eosin (H&E). Then the changes of count and diameter in parietal cells were observed via light microscopy and Image Tools III. Results of this study after analysis showed the significant changes in parietal cells count (mean 61. 3±4. 32) and its diameters (mean 16. 12±1. 18 µm) in L-NAME group in comparison to control and the sham groups in pregnant rats (P≤0. 05). Results of this study showed L-NAME with effects on NO synthesis can reduce the count of parietal cells and increase its diameter in pregnant rats and has destructive effects on structure of stomach parietal cells in pregnancy rats.