Effects of Testosterone on the Intracavernosally Injected Embryonic Stem Cells in Rat / 대한남성과학회지

ABSTRACT

PURPOSE: Stem cell-based cell therapy has recently been tried as a way to restore cavernosal function in an animal model. The aim of this study was to elucidate the role of testosterone on intracavernosally injected embryonic stem cells (ESCs) in rat. MATERIALS AND METHODS: Male Sprague Dawley rats(12 weeks old; n=25) were divided into five groups control, castration, ESC injection after castration, testosterone supplementation after castration, and ESC injection with testosterone supplementation after castration(n=5 in each group). ESCs were transfected with firefly luciferase attached to adenovirus and then injected intracavernously. Testosterone propionate(0.1 mg) was subcutaneously injected daily in the testosterone supplementation group. Cell survival was assessed by optical molecular imaging the day after the ESC injection. After 4 weeks of treatment, intracavernosal pressure and systemic arterial pressure were recorded after pelvic nerve stimulation. Serum testosterone levels were measured by radioimmunoassay. RESULTS: With optical molecular imaging, we observed fluorescent signals around the external genitalia of all ESC-injected animals. The percentage of intracavernosal pressure/systolic blood pressure was significantly lower in the castration group(15.9+/-5.3%) compared to the control group(53.7+/-9.7%)(p0.05). The ESC injection with testosterone supplementation group(54.2+/-4.3%) showed erectile function similar to the control group. CONCLUSIONS: Intracavernosal injection of embryonic stem cells did not improve erectile function in the castrated rat. This result implies that testosterone may play an essential role in the proliferation of stem cells in the corpus cavernosum.