Biochemical changes in cavernosal tissue caused by single sided cavernosal nerve resection and the effects of alpha lipoic acid on these changes

Objective: One of the most important complications of radical prostatectomy operation is erectile disfunction (ED). Oxidative stress patterns and apoptotic changes may happen in smooth muscles and endothelial cells of corpus cavernosum after neuropraxia or neurectomy. Alpha lipoic acid (ALA) shows its antioxidant properties by eliminating free radicals. In this experimental study we investigated the effects of ALA on rehabilitation of cavernosal tissue and nitric oxide synthase (NOS) containing nerve fibers on erectile tissue. Materials and methods: In this study four groups were formed by inclusion of 63 adult fertile rats. Control group (n: 9), sham operation group (n: 18), 18 rats underwent unilateral neurectomy of a 5-mm. segment of the cavernous nerve (group DI) and another 18 rats group which ALA received after unilateral neurectomy (group DII). Assessments were done 3 weeks after neurectomy. Results: We assessed number of NOS containing nerve fibers via nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase staining. According to NADPH diaphorase staining group DII significantly recovered comparing group DI (48.89 +/- 19.00 and 17.22 +/- 6.67 respectively) (p < 0.05). SOD activity is reduced in both; group DI and group DII (31.42 +/- 6.06 and 40.38 +/- 4.24). Nitrite+nitrate levels were elevated significantly in both group DI and group DII (0.52 +/- 0.05 and 0.44 +/- 0.02 micromole/gr wet tissue respectively) when compared with other groups (p < 0.05). There is no statistical difference between results of group DI and Group DII (p > 0.05). Conclusion: This study confirms that neurectomy caused decrease of intracavernous pressure and number of NOS fibers. Neurectomy and surgical trauma caused oxidative stress in rat corpus cavemosum. As a potent antioxidant ALA has positive effects on cavernosal tissue regeneration and rehabilitation by reducing oxidative stress. In this aspect, ALA may have a potential advantage in penile rehabilitation after radical prostatectomy. (C) 2010 AEU. Published by Elsevier Espana, S.L. All rights reserved.