Effects of intracavernosal calcium channel blockers in dogs

Abstract

Intracavernous injection of smooth muscle relaxing agents can induce penile erection. In this experimental study, we compared the effects of intracavernosally injected calcium channel blockers (CCBs) and papaverine in dogs, and investigated their clinical applicabilities. We administered 30 mg papaverine, 10 mg nifedipine, 10 mg nitrendipine and 2.5 mg verapamil to 10 adult male dogs intracavernosally, each at different times. Intracavernous pressure values, systemic arterial pressure values and heart rate values were recorded for 45 minutes alter the intracavernosal injections. We used 'paired student-t test' for statistical analysis. Papaverine induced full erection in all of the 10 dogs. Nifedipine induced full erection in 4, nitrendipine in 5, and verapamil in 6 of the 10 dogs. Nifedipine and nitrendipine caused significant decreases in blood pressure and increases in heart rates. In conclusion, the effects of intracavernosal CCBs are not superior than those of papaverine. We can not recommend nifedipine and nitrendipine for intracavernosal injections, but verapamil may be included in intracavernous pharmacotherapeutic combinations.