Temple Jennifer L, Bradshaw Heather B, Wood Elizabeth, Berkley Karen J
Program in Neuroscience, Florida State University, Tallahassee, FL 32306-1270, USA.
Pain. 1999 Aug;Suppl 6:S13-S20. doi: 10.1016/S0304-3959(99)00133-5.
Anatomical data indicate that the rat uterine horn is innervated primarily by afferent fibers in the hypogastric nerves, suggesting that hypogastric neurectomy, but not pelvic or pudendal neurectomy, should eliminate behavioral responses to uterine horn stimulation. To test this hypothesis, detection and escape responses of rats to different volumes of uterine horn distention (via an indwelling intrauterine balloon) were compared before and after bilateral hypogastric (n = 9), sham-hypogastric (n = 3), pelvic (n = 3), or pudendal (n = 2) neurectomies. As predicted, sham-hypogastric, pelvic, and pudendal neurectomies had no effect on the rats' responses. However, although hypogastric neurectomy completely eliminated responses in five rats whose postmortem evaluation revealed no signs that the uterine balloons had evoked any pelvic pathophysiology, the neurectomy had no effect on the responses of an additional four rats. Postmortem evaluation of these rats revealed gross signs of severe pathology in the vicinity of the balloon in two rats, and evidence that the balloon had shifted caudally so that it was stimulating the cervix rather than the uterine horn in a third. In the fourth rat, pathophysiology had been deliberately induced by the prior implantation of a small pellet that released approximately 1 microg/day of prostaglandin PF2alpha over the uterine horn. Similar findings have been reported in clinical studies on the efficacy of hypogastric ('presacral') neurectomy for dysmenorrhea. Together, the findings support the hypothesis that the major source of afferent innervation of the uterine horn in healthy rats and women is the hypogastric nerve but that the situation changes under conditions of pelvic pathology. Such changes could include additional activation of afferent fibers in nerves that supply other pelvic organs, activation by the uterine pathophysiology of latent uterine innervation from afferent fibers in the pelvic, vagus or ovarian plexus nerves, or some form of central sensitization.
解剖学数据表明，大鼠子宫角主要由腹下神经中的传入纤维支配，这表明腹下神经切除术而非盆腔或阴部神经切除术应能消除对子宫角刺激的行为反应。为验证这一假设，比较了双侧腹下神经切除术（n = 9）、假腹下神经切除术（n = 3）、盆腔神经切除术（n = 3）或阴部神经切除术（n = 2）前后大鼠对不同体积子宫角扩张（通过留置子宫内球囊）的检测和逃避反应。如预期的那样，假腹下神经切除术、盆腔神经切除术和阴部神经切除术对大鼠的反应没有影响。然而，尽管腹下神经切除术完全消除了五只大鼠的反应，其死后评估显示没有迹象表明子宫球囊引发了任何盆腔病理生理学变化，但该神经切除术对另外四只大鼠的反应没有影响。对这些大鼠的死后评估显示，两只大鼠球囊附近有严重病理的明显迹象，第三只大鼠有证据表明球囊已向尾侧移位，以至于它刺激的是宫颈而非子宫角。在第四只大鼠中，先前在子宫角植入了一个每天释放约1微克前列腺素PF2α的小丸，故意诱发了病理生理学变化。关于腹下神经切除术（“骶前”神经切除术）治疗痛经疗效的临床研究也报告了类似的发现。总之，这些发现支持了这样一种假设，即健康大鼠和女性子宫角传入神经支配的主要来源是腹下神经，但在盆腔病理状态下情况会发生变化。这种变化可能包括供应其他盆腔器官的神经中传入纤维的额外激活、盆腔、迷走神经或卵巢丛神经中传入纤维对潜在子宫神经支配的子宫病理生理学激活，或某种形式的中枢敏化。
