Akademik Veri Yönetim Sistemi
Turk Uroloji Dergisi, cilt.30, sa.4, ss.398-404, 2004 (Scopus)
Introduction: Since radical prostatectomy is begun to be performed widely, complications of this surgery like erectyl disfunction is also widely seen. Nonadrengic noncholinerjic (NANC) nervous system is the principal pathway for penile erection and its main neurotransmitter is nitric oxide (NO). Since NO has a gaseous nature and has short half live it can only be detected indirectly. NO is synthetized from L-arginine by Nitric Oxide Sythetase (NOS) and Nicotinamide Adenine Dinucloit Phosphate (NADPH) is used as cofactor in this process. Since NADPH histochemistry is similar to NOS, NADPH diaphorase technique is used to demonstrate NOS containing nevre fibres. Cavernous nerve injury is an important reason for erectly dysfunction following radical pelvic surgeries like radical prostatectomy for prostate cancer. A better understanding of the penile neuroanatomy has enabled urologists to perform nerve-sparing surgery. On the other hand, erectly dysfunction is reported in 18-60% of men even after bilateral nerve sparing surgery. B vitamins are shown to be affective on nerve regeneration on axons and myelin sheets. In the present experiment, we studied the effect of unilateral cavernous nerve neurotomy to NO containing nerve fibres of the Sprage-Dawley rats and B vitamin complex on erectly tissue regeneration. Materials and Methods: Experiments were performed on sixty-three (63) male fertile adult Sprague-Dawley rats (aged 60-90 days, 250-300 gm.), divided into 4 groups; as group I, control composed of 9 rats (n=9), group II, sham operation composed of 18 rats (n=18), unilateral cavernous nerve neurotomy (group DI) (n=18), and unilateral cavernous nerve neurotomy with B vitamin complex (B1, B6, and B12) (group DII) (n=18). Functional evaluation and tissue procurement were performed after 3 weeks and 6 months postoperatively for each groups except control group. Functional evaluation was performed by measuring corpus cavernousum pressure after direct electro stimulation of contra lateral intact cavernous nerves. After functional evaluation 3 mm segment was removed from mid-shaft penile segment and tissue is stained for NADPH diaphorase and investigated by light microscope. The staining pattern was assessed by counting the number of NADPH-positive regions within each corpus cavernosum in 2 arbitrary areas (magnification x400). Data were compared vidth the non-parametric Kruskal-Wallis and Mann-Whitney U tests for unpaired samples. Values were considered significant at p≤0.05. Results: Electro stimulation of the cavernous nerve revealed in the mean maximal intracavernous pressure of sham group 70.2±6.4 and 77.4±7.1 cm H2O at 3 weeks and at 6 months respectively. Electro stimulation of the intact cavernous nerve showed in the mean maximal intracavernous pressure of unilateral neurotomy group (group DI) 33.8±16.9 and 58.8±12.9 cm H2O at 3 weeks and 6 months respectively and the mean maximal intracavernous pressure of unilateral neurotomy with B vitamin complex group (group DII) 35±14,3 and 56,3±15,8 cm HO2 at 3 weeks and 6 months respectively. NADPH-Diaphorase staining of mid-shaft speciments at 3 weeks revealed that the number of NOS-containing nerve fibres per corpus cavernosum was significantly decreased in neurotomy groups (group DI and group DII) than control and sham groups (p≤0.05). Staining was similar among group DI (unilateral neurotomy) and group DII (unilateral neurotomy with B vitamin complex) (p≥0.05). At 6 months, in neurotomy groups, there is a slight increase in staining when compared with the findings at 3 weeks. The staining was similar among group DI (unilateral neurotomy) and group DII (unilateral neurotomy with B vitamin complex) (p≥0.05) and in control and sham groups both at 3 weeks and 6 months (p≥0.05). Conclusion: Even unilateral nerve injury has negative effect on corpus cavernousum and may cause erectly dysfunction. In rats, erectly function may improve at 6 months following unilateral nerve injury but complete recover cannot occur. B vitamin complex has not any effect on this improvement.