Carrier S, Zvara P, Nunes L, Kour N W, Rehman J, Lue T F
Department of Urology, University of California School of Medicine, San Francisco, USA.
J Urol. 1995 May;153(5):1722-7.
In patients who recover erectile function after radical prostatectomy (with preservation of at least 1 neurovascular bundle), a recovery time of 6 to 18 months is not uncommon. As this is also the usual time required for regeneration of spinal nerves, we believe that regeneration of cavernous nerves, partially damaged inadvertently, may be responsible. In a rat model, we examined the long-term effect of unilateral and bilateral cavernous nerve transection on the nonadrenergic/noncholinergic (NANC) nervous system and erectile function. In 31 rats, nitric oxide synthase (NOS), the enzyme that catalyzes nitric oxide production, was identified in penile nerve fibers from a mid-shaft segment with nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase staining and antibody to neuronal NOS. Animals were divided into three groups: 5 rats underwent pelvic exploration without transection of cavernous nerves (sham group); 13 rats underwent unilateral neurotomy of a 5-mm. segment of the cavernous nerve; and 13 rats underwent bilateral neurotomy. After bilateral ablation, the NOS-positive nerve fibers were significantly decreased at 3 weeks and remained so at 6 months; no erectile response could be elicited by pelvic nerve stimulation. After unilateral ablation, the NOS-positive nerve fibers were similarly decreased on the side of the neurotomy at 3 weeks, but by 6 months the number had increased significantly and approximated the level on the contralateral side. Furthermore, electrostimulation of the intact side induced a greater intracavernous pressure response at 6 months than at 3 weeks (N.B. the rat has an incomplete septum). Fibers positive for NOS were also identified in the dorsal nerve. The staining pattern diminished as rapidly and significantly on the side of neurotomy as in tissue from the corpus cavernosum. However, regeneration was not seen. To our knowledge, this is the first demonstration of regeneration of NOS-containing nerves after cavernous nerve neurotomy. Our findings support the reports by others that unilateral nerve-sparing is sufficient to preserve erectile function.
在根治性前列腺切除术后恢复勃起功能的患者（至少保留1条神经血管束）中，6至18个月的恢复时间并不罕见。由于这也是脊神经再生所需的通常时间，我们认为海绵体神经的再生可能是导致这种情况的原因，海绵体神经在手术中可能会被意外部分损伤。在大鼠模型中，我们研究了单侧和双侧海绵体神经切断对非肾上腺素能/非胆碱能（NANC）神经系统和勃起功能的长期影响。在31只大鼠中，用烟酰胺腺嘌呤二核苷酸磷酸（NADPH）黄递酶染色和神经元型一氧化氮合酶抗体，在阴茎中段神经纤维中鉴定出催化一氧化氮生成的一氧化氮合酶（NOS）。动物被分为三组：5只大鼠接受盆腔探查但不切断海绵体神经（假手术组）；13只大鼠接受5毫米海绵体神经节段的单侧神经切断术；13只大鼠接受双侧神经切断术。双侧切除后，NOS阳性神经纤维在3周时显著减少，并在6个月时仍保持减少状态；盆腔神经刺激不能诱发勃起反应。单侧切除后，NOS阳性神经纤维在神经切断侧3周时同样减少，但到6个月时数量显著增加，接近对侧水平。此外，在6个月时，对完整侧进行电刺激诱发的海绵体内压反应比3周时更大（注意，大鼠有不完全的隔膜）。在背神经中也鉴定出NOS阳性纤维。神经切断侧的染色模式与海绵体组织一样迅速且显著减弱。然而，未见再生。据我们所知，这是首次证明海绵体神经切断术后含NOS神经的再生。我们的研究结果支持了其他人的报告，即保留单侧神经足以维持勃起功能。
