The present study tested whether the topical application of a local anesthetic (Lidocaine) to the vaginocervical region altered the pattern of paced mating behavior displayed by gonadectomized, hormone-primed female rats. Both rats receiving Lidocaine and rats receiving vehicle exhibited the expected lengthening of contact-return latency as the intensity of the mating stimuli increased (mount < intromission < ejaculation). Although rats given Lidocaine versus vehicle received a greater number of intromissions, no other group differences were observed. The present study found no evidence for a change in behavioral responsiveness following the vaginocervical application of Lidocaine.

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.

No abstract