Growth hormone enhances regeneration of cavernous nerves after their transplantation in rats / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the effect of growth hormone (GH) on penile erection after reconstruction of cavernous nerves using sural nerve as an interposition nerve graft in rats.</p><p><b>METHODS</b>Twenty-four male Sprague-Dawley rats (3-4 ms of age and 300-400 g in weight) were randomly divided into 2 groups: nerve graft group and GH group, each electrostimulated to determine the erectile potency 2 and 4 months after nerve graft (followed by hypodermic GH injection). The nNOS-positive nerve fibers in the corpora cavemosa were examined by streptavidin-peroxidase immunohistochemistry technique (SP method). Image analysis was used to calculate the area stained in pixel.</p><p><b>RESULTS</b>Electrostimulation at 2 months produced 31.25% of erections in the GH group but none in the grafted rats. There was a significant difference in the erection rate produced by electrostimulation between the two groups at 2 months (P < 0.05). The pixel of the expression of nNOS-positive nerve fibers in the GH group (38971 +/- 7692) was also greater than that of the graft group (16538 +/- 3179, P < 0.05). At 4 months, 43.75% of the graft group and 75% of the GH group produced erections upon electrostimulation, with no significant difference between the two groups (P > 0.05). The pixels of the expression of nNOS-positive nerve fibers were 79276 +/- 12,021 and 91348 +/- 18965, respectively (P > 0.05).</p><p><b>CONCLUSION</b>GH can accelerate the regeneration of cavernous nerves after bilateral nerve grafting, and GH administration may present a new physiological approach to the treatment of erectile dysfunction after radical pelvic surgery.</p>

Effects on erectile function of transplanted major pelvic ganglion into the corpus cavernosum of adult rats with bilateral cavernous nerve injury / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the effects on erectile function of transplanted major pelvic ganglion into the corpus cavernosum of adult male rats undergoing transection of bilateral cavernous nerves.</p><p><b>METHODS</b>Twenty-six male Sprague-Dawley rats (3 - 4 month-old and 300 - 400 g/each) were divided into 2 groups: experimental group (transection of bilateral cavernous nerves and transplantation of left ganglion into left crus of penis, n = 16) and control group (transection of bilateral cavernous nerves only, n = 10). Erectile function was measured by injecting APO, and intracavernous pressure was measured 1 and 3 months afterwards by electric-stimulating the right major pelvic ganglion or the left crus. Half animals in each group were sacrificed 1 and 3 months afterwards for detecting nNOS-containing nerve fibers of corpus cavernosum. Electron microscopy of the implanted area was performed to assess neuronal survival.</p><p><b>RESULTS</b>Both of the two groups have no erectile response to APO injection. Electrostimulation on the right major pelvic ganglion and left crus failed to produce erection in experimental group. The mean pressure changes in the two groups, measured by stimulating the left crus, were (9.41 +/- 3.20) and (4.16 +/- 2.58) cmH(2)O 1 month afterwards, and (13.67 +/- 4.18) and (5.09 +/- 2.74) cmH(2)O 3 months afterwards, respectively (P < 0.05). An increased number of nNOS-containing nerve fibers in left crus was detected in experimental group 1 and 3 months later, compared with control one (218.7 +/- 24.5, 18.0 +/- 3.7; 183.2 +/- 19.7, 19.0 +/- 3.8; P < 0.05). Ultrastructure examination by transmission electron microscope confirmed the survival of the implanted ganglion.</p><p><b>CONCLUSION</b>Major pelvic ganglion can survive in the corpus cavernosum, and it has significant effects on the number of nNOS-containing nerve fibers and the alteration of intracavernous pressure.</p>