Korean J Androl.  2007 Dec;25(3):129-134.

Effects of Chronic Treatment with a Type 5 Phosphodiesterase Inhibitor on Erectile Function in Diabetic Rats

• Cho MC
• Park K
• Paick JS

Abstract

PURPOSE: We investigated whether chronic treatment with a type 5 phosphodiesterase inhibitor (PDE5I) could suppress corporal apoptosis and improve erectile function in diabetic erectile dysfunction.
MATERIALS AND METHODS
Sprague-Dawley rats (12 weeks old) were assigned into 1) normal control 2) diabetes, and 3) diabetes with PDE5I treatment groups (n=12 per group). After inducing diabetes with intraperitoneal injection of streptozotocin, the diabetic and PDE5I-treatment groups were treated with vehicle or PDE5I (mirodenafil, 10 mg/kg) for 4 weeks. To examine the effect on erectile response, 6 rats in each group underwent cavernosometry under cavernous nerve electrostimulation (2 V, 0.2 msec, 50 sec, 2.5~20 Hz). The penile tissues from the remaining 6 rats were used for immunohistochemical evaluation of apoptosis.
RESULTS
The diabetic group showed markedly lower mean intracavernosal pressure/mean arterial pressure (ICP/MAP) and area under the curve of cavernosometry than normal controls, whereas the diabetes with PDE5I treatment group showed normal results. Despite persistent hyperglycemia, PDE5I treatment significantly reduced the mean apoptotic index (39.6+/-4.6 vs 21.8+/-5.1, p<0.05).
CONCLUSIONS
Chronic administration of PDE5I suppressed apoptosis of corporal smooth muscle and improved erectile function in a rat model of diabetic erectile dysfunction.

Keyword

Rat; Diabetes; Erectile dysfunction; Phosphodiesterase inhibitor

MeSH Terms

Animals
Apoptosis
Arterial Pressure
Erectile Dysfunction
Hyperglycemia
Injections, Intraperitoneal
Male
Models, Animal
Muscle, Smooth
Rats*
Rats, Sprague-Dawley
Streptozocin
Streptozocin