The Effects of Sodium Pentobarbital or Ether Anesthesia on Spontaneous and Electrochemically-lnduced Gonadotropin Release

SummaryThese studies have examined the effects of sodium pentobarbital or ether anesthesia on temporal plasma patterns and concentrations of FSH and LH following electrochemical stimulation (ECS) of the medial preoptic area (MPOA) or dorsal anterior hypothalamic area (DAHA) in proestrous rats. The injection of sodium pentobarbital at 1245 on proes-trus and ECS of either the MPOA or DAHA at 1300 elicited a rise in plasma FSH 120 min poststimulation. Injection of this barbiturate at 1245 and ECS of either region at 1500, when the effects of anesthesia had begun to wane, reduced the time interval between stimulation and the first significant plasma FSH rise to 60 min. A third group of proestrous rats was anesthetized with ether at 1100 and the DAHA or the MPOA was electrochemically stimulated. In such preparations, FSH in plasma rose significantly 60 min post-stimulation. In all MPOA-electrochemically stimulated groups, the first significant rise in plasma LH occurred 30 min poststimulation regardless of the...