Clarnette T D, Hutson J M, Beasley S W
F. Douglas Stephens Surgical Research Laboratory, Royal Children's Hospital, Melbourne, Victoria, Australia.
J Urol. 1996 Oct;156(4):1463-6.
We examined the factors that influence development of the processus vaginalis in the rat.
Neonatal Sprague-Dawley rats 0 to 3 days old underwent distal or proximal gubernaculotomy, unilateral orchiectomy or proximal genitofemoral nerve transection. At ages 28 to 60 days the rats were sacrificed, position of the testis was noted and length of the processus vaginalis was measured.
There was no development of the processus vaginalis after distal gubernaculotomy. Proximal gubernaculotomy enabled the processus vaginalis to achieve a mean length similar to that of controls (p = 0.06) when the testis descended into the scrotum. Mean length of the processus after proximal gubernaculotomy with an abdominal testis, surgical orchiectomy and torsion of the testis after proximal gubernaculotomy was similar (p = 0.9) but less than that of controls (p < 0.05). Proximal division of the genitofemoral nerve produced variable results depending on how and when the surgical procedure was performed, and whether the psoas muscle was divided.
Distal attachment of the gubernaculum is essential for normal development of the processus vaginalis. Distal gubernaculotomy prevents development of the processus vaginalis because of mechanical disruption of the gubernaculum. Proximal attachment is not essential for normal development of the processus vaginalis but it serves to anchor the testis to the region of the internal inguinal ring, allowing intra-abdominal pressure to facilitate descent of the testis. In the presence of an innervated gubernaculum the processus vaginalis achieves greater length when the testis descends into the scrotum, suggesting that its complete development demands the presence of a testis in the sac. The timing of genitofemoral nerve division may be crucial in determining the subsequent effect on the development of the processus vaginalis and testicular descent, since programming of the gubernaculum by calcitonin gene-related peptide released from the genitofemoral nerve appears to occur just before birth in the rat.
我们研究了影响大鼠鞘突发育的因素。
对0至3日龄的新生斯普拉格-道利大鼠进行远端或近端睾丸引带切断术、单侧睾丸切除术或近端生殖股神经切断术。在28至60日龄时处死大鼠，记录睾丸位置并测量鞘突长度。
远端睾丸引带切断术后鞘突未发育。当睾丸降至阴囊时，近端睾丸引带切断术使鞘突的平均长度达到与对照组相似的水平（p = 0.06）。近端睾丸引带切断术伴腹腔内睾丸、手术切除睾丸以及近端睾丸引带切断术后睾丸扭转后鞘突的平均长度相似（p = 0.9），但小于对照组（p < 0.05）。近端生殖股神经切断术的结果因手术方式、时间以及腰大肌是否被切断而异。
睾丸引带的远端附着对于鞘突的正常发育至关重要。远端睾丸引带切断术因睾丸引带的机械性中断而阻止鞘突发育。近端附着对于鞘突的正常发育并非必不可少，但它有助于将睾丸固定在内环区域，使腹腔内压力促进睾丸下降。当睾丸降至阴囊时，在有神经支配的睾丸引带存在的情况下，鞘突能达到更长的长度，这表明其完全发育需要阴囊内有睾丸存在。生殖股神经切断的时机对于确定其随后对鞘突发育和睾丸下降的影响可能至关重要，因为从生殖股神经释放的降钙素基因相关肽对睾丸引带的编程似乎在大鼠出生前就已发生。
