Sildenafil Effect on Atrial Natriuretic Peptide Level in Pulmonary Hypertensive Rats.

BACKGROUND

Pulmonary Hypertension (PH) leads to changes in pulmonary vascular architecture, hypertrophy of the right ventricle, and heart failure. Sildenafil is a drug that can modulate PH by inducing smooth muscle relaxation and vasodilation.

AIMS: To investigate the ability of sildenafil to alleviate the monocritaline (MCT)-induced PH in rats and to estimate the role and its effect on the atrial natriuretic peptide (ANP) levels.

METHODS

28 adult male rats were divided randomly into four groups: Group A (control group; n=7). Group B (MCT-treated group; n=7) was given a single dose of MCT 60 mg/kg subcutaneously. Group C (The reversal group; n=7) received a single dose of MCT 60 mg/kg subcutaneously for three weeks and then sildenafil at 50 mg/kg/day, given daily for another three weeks. Group D (The prevention group; n=7) simultaneously received a single dose of MCT 60 mg/kg subcutaneously and sildenafil daily at 50 mg/kg for three weeks.

RESULTS

The animals in the prevention group showed a significant decrease in ANP levels compared to the reversal and MCT-treated groups. This decrease was associated with a significant reduction in the Fulton index ratio in the prevention group compared to the reversal group. The nitric oxide levels were also significantly higher in the reversal group than in the control group.

CONCLUSION

Preventive sildenafil treatment was associated with a significant decrease in ANP levels and reduced MCT-induced cardiac hypertrophy in rats.