Pelvic Neurectomy Research Articles

Experimental studies on the acetylcholinesterase-positive nerves in the ovary of the rat.

Adrenergic and acetylcholinesterase (AChE)-positive nerves were studied in the rat ovary four days after various experimental denervation procedures. Ablation of pelvic parasympathetic nerves (pelvic neurectomy [PN]) or abdominal vagotomy (AV) had no obvious affect on the adrenergic of AChE-positive nerves in the ovary. Section of the mesovarium resulted in the loss of all histochemically demonstrable adrenergic and AChE-positive nerves. Chemical sympathectomy with 6-hydroxydopamine (6-HD) resulted in the loss of all histochemically demonstrable adrenergic nerves. A few AChE-positive nerves remained in the hilar and medullary regions following chemical sympathectomy. When the presumptive parasympathectomy procedures (AV and PN) were combined with chemical sympathectomy, again no adrenergic nerves remained, however a few hilar and medullary AChE-positive fibers persisted after sympathectomy plus PN, but no AChD-positive fibers were demonstrable in the AV plus 6-HD group. These findings show that most of the AChE- in ovarian nerves is localized in adrenergic nerves. It is suggested that the few AChE-positive fibers remaining in the ovarian hilar area after 6-HD treatment of 6-HD plus PN are derived from the vagus. These few AChE-positive nerves may be postganglionic vagal parasympathetic or they may be sensory fibers.

Effects of chronic deafferentation on adrenergic ganglion cells and small intensely fluorescent cells.

To determine the reaction of adrenergic ganglion cells and small intensely fluorescent (SIF) cells to chronic deafferentation, catecholamine fluorescence of the major pelvic ganglion (MPG) of the rat has been studied following section of the hypogastric nerve, pelvic nerve and sympathetic trunk. Only minor changes occurred following section of the hypogastric nerve; the fluorescence surrounding a few adrenergic ganglion cells became brighter. In contrast, pelvic neurectomy resulted in the appearance of numerous varicose fibres and an increase in the fluorescent intensity of fibres enclosing many ganglion cells. Varicose fibres seem to originate from adrenergic ganglion cells and SIF cells. In many instances, nests of SIF cells gave rise to radially oriented fibres. Removal of the sympathetic trunk appeared to have no effect on the MPG. It is suggested that the appearance of varicose fibres from SIF cells following deafferentation may be due to collateral sprouting of these cells or to the increased fluorescence of pre-existing processes.

The Influence of Coitus, Suckling, and Prolactin Injections on Pregnancy in Pelvic Neurectomized Rats

SummaryBilateral resection of the pelvic nerve (PN) in female rats had no effect on the estrous cycle, but prevented pregnancy when performed prior to mating. Pelvic neurectomy performed 30 min postmating did not affect the interim pregnancy, but blocked parturition. Twice daily sc injections of 7.0 to 28 IU of prolactin (NIH-S-8) into PN females beginning on the a.m. after mating (day 1) maintained normal pregnancy until sacrifice at day 16. Lower doses of 1.4 and 3.5 IU of prolactin twice daily were partially effective; whereas a single injection of 280 IU on day 1 was ineffective. Injections of 7.0 IU of prolactin on days 1-3 maintained pregnancy in 60% of the PN females. Following parturition, lactating females suckling six young were bilaterally pelvic neurectomized and mated to a fertile male. Pregnancy occurred and was maintained in 7 of 10 females, sacrificed at day 16 postpartum. Removal of the entire litter at day 1, 3, or 6 postpartum, resulted in maintenance of pregnancy in two of eight, three...

Studies on the relation of decidual cell response to luteal maintenance in the pseudopregnant rat.

The relation of the decidual cell response (DCR) to the life span of corpora lutea was studied in three experiments on pseudopregnant rats. The first experiment with five groups of 12 rats each was conducted to see if there was a local effect of a DCR on luteal maintenance. The DCR was induced on Day 4 of pseudopregnancy (morning of vaginal plug = Day 0). The groups and mean lengths of pseudopregnancy (in days) were as follows: (I) sham operation: 14.3; (II) unilateral DCR: 18.4; (III) bilateral DCR: 19.4; (IV) unilateral DCR and ipsilateral unilateral ovariectomy: 14.7; (V) unilateral DCR and contralateral unilateral ovariectomy: 18.2. Groups II,III, and V differed (p < .05) from groups I and III but not from each other. A second experiment showed that pelvic neurectomy did not abolish the increase in luteal life span due to either hysterectomy or a bilateral DCR in rats. A third experiment was performed to determine if uterine distention without a DCR would alter the length of pseudopregnancy. Cylindrical glass rods were placed in one or both uterine horns on Day 1 of pseudopregnancy. No differences in the mean length of pseudopregnancy were detected when these two groups were compared with controls. It was concluded that the DCR has a local effect on the life span of corpora lutea, and that the lengthening of pseudopregnancy due to a DCR was not abolished by pelvic neurectomy, and was not the result of uterine distention.

Role of the pelvic nerve vs. the abdominal sympathetic nerves in the reproductive function of the female rat.

The anatomy of the pelvic nerve (nervus erigens, pelvic parasympathetic nerve) is described for the rat. This nerve carries the afferents responsible for the induction of pseudopregnancy since the animals did not respond to mechanical cervical stimuli or to mating stimuli after bilateral pelvic neurectomy. However, the fertile eggs produced by such mating implanted normally, and developed to term fetuses when these neurectomized animals were made pseudopregnant by administration of a single injection of reserpine (1 mg/kg) on Day 1. These neurectomized animals were unable to deliver their litters spontaneously. Massive deciduoma formation could be elicited in pseudopregnant pelvic-neurectomized animals. The prolongation of pseudopregnancy, known to accompany this growth, did not occur, however. This suggests that the deciduoma-bearing uterus extends the pseudopregnancy by a neurogenic stimulus rather than by a hormonal one. Extensive abdominal sympathectomy was compatible with all phases of pregnancy, fro...

Pelvic Autonomic Neurectomy for Ulcerative Colitis

Pelvic Autonomic Neurectomy for Ulcerative Colitis