Background and Objective: Impairment in nitric oxide (NO) production can culminate in pathological conditions, such as pulmonary hypertension, acute respiratory distress syndrome (ARDS), and chronic obstructive pulmonary disease (COPD). The present study aimed to investigate the effects of L-arginine and L-nitro-arginine methyl ester (L-NAME) on the diameter and number of pulmonary alveoli in female rats.
Methods: In this experimental study, 32 female Sprague-Dawley rats, aged 8 weeks and weighing 200–250 g, were randomly divided into four groups of eight. Group 1 received normal saline (2 ml/kg body weight [BW]), Group 2 received L-arginine (200 mg/kg BW), Group 3 received L-NAME (20 mg/kg BW), and Group 4 received a combination of L-arginine (200 mg/kg BW) and L-NAME (20 mg/kg BW) via intraperitoneal injection for two weeks. The animals were then anesthetized, and their lungs were excised. After fixation and tissue processing, histological sections were stained with hematoxylin and eosin (H&E) to evaluate the resulting changes. To obtain quantitative data regarding the diameter and number of alveoli, ImageTool III software was utilized.
Results: Injection of L-NAME and L-Arginine led to a non-significant decrease in the mean diameter of pulmonary alveoli. L-Arginine exerted the greatest effect and L-NAME had the least effect on the number of pulmonary alveoli; however, these changes were not statistically significant.
Conclusion: Injection of L-Arginine and L-NAME had no significant effect on the diameter and number of pulmonary alveoli in female rats.