CNS Depression in the Absence of Prolactin Release Following Intraarterial Injections of Sodium Pentothal in the Proestrous Rat 1

Summary

Samples of whole blood were collected at 20–min intervals for a period of several hours from individual cannulated proestrous rat. Plasma luteinizing hormone and prolactin concentrations were determined by radioimmunoassay. Either pentobarbital or pentothal anesthesia maintained during the critical period in proestrus rats blocked the preovulatory increase in serum LH and prevented subsequent ovulation. Pentobarbital anesthesia induced a rapid increase in serum prolactin concentrations whereas pentothal anesthesia did not, but both anesthetics prevented the spontaneous preovulatory increase in serum prolactin. In addition, pentothal anesthesia prevented the response to subsequent injections of pentobarbital.