The display of paced mating behavior in a rat model of endometriosis.

Endometriosis is a disorder associated with chronic pelvic pain and ill effects on women's sexual health. The present study examined the effects of pelvic endometriotic implants on the display of paced mating behavior in female rats. Approximately 2 months after the surgical induction of endometriosis, rats were tested for paced mating behavior during proestrus (Experiment 1) or after bilateral ovariectomy and hormone replacement (Experiment 2). Although endometriotic implants were confirmed at autopsy, rats with surgical endometriosis in both experiments exhibited normal patterns of paced mating behavior. The positive relationship between implant material and contact-return latency following ejaculation in Experiment 2 suggests that the sensitivity to vigorous mating stimulation may be influenced by endometriosis.

Genitosensory nerve modulation of paced mating behavior: evidence for pelvic, but not hypogastric, nerve influence.

The pelvic nerve is known to play a role in the behavioral and neurochemical responses exhibited during paced mating behavior. The present study extended the analysis of the contribution of the genitosensory nerves to the display of paced mating behavior to include bilateral hypogastric nerve transection, bilateral pelvic nerve transection, or transection of both the hypogastric and pelvic nerves. Rats with pelvic nerve transection were less likely to exit the male compartment, took longer to exit the male compartment following intromissions, and returned to the male more quickly following intromissions compared to rats with an intact pelvic nerve. In contrast, hypogastric nerve transection alone did not affect paced mating and had no modulating effect on the paced mating behavior of rats with pelvic nerve transection. Our results support the view that key aspects of paced mating behavior are modulated by signals transmitted via the pelvic nerve, without any discernable contribution from the hypogastric nerve.