Long-term treatment of clonidine, atenolol, amlodipine and dihydrochlorothiazide, but not enalapril, impairs the sexual function in male spontaneously hypertensive rats.

This study was designed to investigate the impact of representative antihypertensive drugs of 5 classes on the sexual function in male spontaneously hypertensive rats (SHR) at doses that achieved similar blood pressure (BP) reduction. The experiment was performed in 6 groups of male SHR. The dose are 20 μg/kg/day for clonidine, 3 mg/kg/day for enalapril, 20 mg/kg/day for atenolol, 2 mg/kg/day for amlodipine, and 10 mg/kg/day for dihydrochlorothiazide. SHR were treated for 3 months, and then the penile erection and sexual behavior were detected. After BP recording, SHR were killed to evaluate the organ-damage, weight of accessory sex organs and levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone in serum. Five drugs had the similar efficacy on BP reduction. All drugs except of enalapril, significantly prolonged the mount latency, and decreased the mount frequency (P<0.05). Clonidine also reduced the conception rate (45% vs. 80% in control group, P<0.05). Amlodipine and dihydrochlorothiazide significantly increased the testosterone level (0.79±0.30, 0.80±0.34 vs. 0.49±0.20 in control group, unit: ng/dl, P<0.05). Enalapril, atenolol and amlodipine also significantly decreased the BP variability (systolic, 8.2±2.5, 7.6±1.8, 8.9±2.0 vs. 12.2±3.8 in control group, unit: mm Hg). All these drugs significantly decreased the organ-damage (P<0.05). In conclusion, long-term treatment with 5 common antihypertensive drugs possessed obvious organ protection in SHR. Clonidine, atenolol, amlodipine and dihydrochlorothiazide, but not enalapril, impair sexual function.