| Abstract: | The effects of pinealectomy or bilateral superior cervical ganglionectomy on serum luteinizing hormone (LH) levels and ovulation were studied in constant estrous-anovulatory rats bearing a frontal hypothalamic deafferentation (FHD). Ovulation returned in 65% of the animals undergoing pinealectomy or bilateral superior cervical ganglionectomy. Almost 50% of these ovulating animals showed elevated serum levels of LH on the day of vaginal proestrus, while the remainder ovulated without appreciable changes in serum LH concentrations. It is suggested that the absence of an LH peak in the latter cases was due to an insufficient sampling size. The results suggest that pinealectomy and cervical sympathectomy may result in LH release by interference with the hypothalamic and brain stem serotonergic system involved in the inhibition of LH release. |
