Effects of a New Selective Phosphodiesterase Type 5 Inhibitor, KJH-1002, on the Relaxation of Rabbit Corpus Cavernosum Tissue

Abstract

The present study examined functional effects of a new selective phosphodiesterase type 5 inhibitor,piperazine (KJH-1002), in the isolated rabbit corpus cavernosum (RCC). Relaxing effects of KJH-1002 were alsocompared with those of sildenafil, which is currently used as an oral therapy for penile erectile dysfunction. In theisolated RCC precontracted with phenylephrine, both KJH-1002 and sildenafil in the concentration range of 1 to1000 nM, produced a comparable potentiation of the electrical field stimulation-induced relaxation in a concen-tration-dependent manner. In the sodium nitroprusside (SNP 50 values, concentrationsof SNP required to produce a 50% relaxation of the phenylephrine-induced contraction, were significantlydecreased to the similar extent by treatments with KJH-1002 and sildenafil. The results suggest that a new selec-tive phosphodiesterase type 5 inhibitor, KJH-1002, has an augmentative effect on penile erection comparable tothat of sildenafil and can be useful for the treatment of erectile dysfunction.Key words □ Penile erection, Rabbit corpus cavernosum, Relaxation, Phosphodiesterase type 5 inhibitor,KJH-1002, Sildenafil