Comparative study between the effects of yohimbine and sildenafil on erectile dysfunction in stressed male rats

ABSTRACT

The incidence of erectile dysfunction increases as a result of stressful conditions such as industrialized lifestyles. Both physical and psychological stress may interfere with the reproductive capacity of several species. In this work stress was induced by immersion of rats in cold water [15 minutes/day] for 14 consecutive days. The effects of yohimbine [0.2mg/Kg, i.p.] and sildenafil [20mg/Kg, i.p] on erectile dysfunction of stressed rats were assessed in comparison with control group. Furthermore the levels of testosterone, LH and FSH in blood were evaluated. Results revealed that, immersion of rats in cold water significantly increased mount, intromission, ejaculation latencies and intercopulatory interval indicating a decrease in sexual arousal and motivation, and also decreased ejaculation frequency indicating a decrease in copulatory performance and potency. In addition immersion of rats in cold water for prolonged period could decrease the copulatory activity as evidenced by mating test and decreased testosterone, LH and FSH levels. Results revealed that treatment with yohimbine or sildenafil significantly increased the sexual arousal and potency and corrected the effects induced by stress on the mating behavior of male rats. On the contrary they did not significantly alter testosterone, follicle stimulating hormone [FSH] and luteinizing hormone [LH] levels