Martínez-Gómez M, Cruz Y, Pacheco P, Aguilar-Roblero R, Hudson R
Centro de Investigaciones Fisiológicas, Universidad Autónoma de Tlaxcala, Mexico.
Physiol Behav. 1998 Mar;63(5):929-32. doi: 10.1016/s0031-9384(97)00530-1.
In the rat the pelvic nerve consists of a viscerocutaneous (sensory) branch which receives information from pelvic viscera and the midline perineal region, and a somatomotor (muscular) branch which innervates the ilio- and pubococcygeous muscles. To investigate the contribution of these branches to the parturition process, the length of gestation and course of delivery were closely monitored in 43 pregnant, Wistar-strain rats randomly assigned to five groups: untreated control animals, animals in which the somatomotor branch of the pelvic nerve was bilaterally sectioned on Day 14 of gestation, animals in which the viscerocutaneous branch of the pelvic nerve was bilaterally sectioned on Day 14 of gestation, animals treated similarly to the previous group but with young delivered by C-section at term, and sham-operated controls. Sectioning the viscerocutaneous branch seriously disrupted parturition and resulted in major dystocia and a high percentage of stillbirths in all females. In contrast, sectioning the somatomotor branch had no apparent effect on parturition and no significant differences were found between females of this group and sham or control dams on any of the measures recorded. It is concluded that the viscerocutaneous branch of the pelvic nerve is vital for the normal course of parturition in the rat but that the somatomotor branch plays little role, if any.
在大鼠中，盆神经由内脏皮肤（感觉）支和躯体运动（肌肉）支组成。内脏皮肤支接收来自盆腔脏器和会阴中线区域的信息，躯体运动支支配髂尾肌和耻骨尾骨肌。为了研究这些分支在分娩过程中的作用，对43只怀孕的Wistar品系大鼠进行了密切监测，这些大鼠被随机分为五组：未处理的对照动物、在妊娠第14天双侧切断盆神经躯体运动支的动物、在妊娠第14天双侧切断盆神经内脏皮肤支的动物、与前一组处理方式相同但足月时通过剖宫产分娩幼崽的动物以及假手术对照组。切断内脏皮肤支严重扰乱了分娩过程，导致所有雌性大鼠出现严重难产和高比例死产。相比之下，切断躯体运动支对分娩没有明显影响，该组雌性大鼠与假手术或对照母鼠在任何记录指标上均无显著差异。结论是，盆神经的内脏皮肤支对大鼠正常分娩过程至关重要，而躯体运动支即使有作用也很小。
