Role of 5-hydroxytryptamine receptors on luteinizing-hormone-releasing hormone release in the ovariectomized, estradiol-treated rat.

The present experiments examined the effect of ketanserin [5-hydroxytryptamine-2 (5-HT2) antagonist] and 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT) (5-HT1 agonist) on the in vitro release of luteinizing-hormone-releasing hormone (LHRH) from the medial basal hypothalamus-preoptic area-suprachiasmatic nucleus region (MBH-POA-SCN) of ovariectomized (OVX), estradiol-(E2) treated rats using in vitro superfusion techniques. Regularly cycling female Holtzman rats (250-300 g) were maintained on a photoperiod of 0500-1900 h light at 22 +/- 2 degrees C. Rats were ovariectomized (25-30 days) and received Silastic E2 implants (150 micrograms E2/ml sesame oil) SC 48 h prior to the in vitro superfusion. Following a control period of Krebs-Ringer Phosphate (KRP) superfusion, ketanserin (5-HT2 receptor antagonist, 1 x 10(-6) M) significantly increased LHRH release (p less than 0.05). Subsequent superfusion of 5-HT (1 x 10(-8) M) significantly decreased (p less than 0.05) the effect of ketanserin on LHRH release. The 5-HT2 antagonist Lilly 53857 (1 x 10(-6) M or 1 x 10(-5) M) did not increase LHRH release above control levels. Neither 5-HT nor quipazine had a significant effect on LHRH release at 1 x 10(-6) M. Superfusion of 8-OH-DPAT (5-HT1 receptor agonist 1 x 10(-5) M) significantly (p less than 0.01) increased LHRH release but subsequent superfusion of 8-OH-DPAT + pindolol (mixed 5-HT1a,1b and a beta-adrenergic receptor antagonist, 1 x 10(-6) M) or pindolol alone had no effect on LHRH release. These results suggest that the 5-HT1 receptor plays a role in LHRH release and this effect may be related to the opposing effects of postsynaptic and autoreceptors. However, the failure of Lilly 53857 to reproduce the stimulatory effect of ketanserin on LHRH release suggests that 5-HT2 receptors in the MBH-POA-SCN may not modify LH release during the estrous cycle.

In vivo 5-HIAA release from the anterior hypothalamus in the ovariectomized and estradiol treated rat following perfusion with progesterone.

In the present study the frequency and magnitude of the release of 5-Hydroxyindoleacetic Acid (5-HIAA) was measured from the anterior hypothalamus of ovariectomized (OVX) and OVX rats treated with estradiol (E2). Female, Holtzman strain rats were maintained on a photoperiod of 14 H light from 0100 to 1500 H and experiments performed from 0900 to 1700 H. Animals exhibiting four-day estrous cycles (250-300 gms) were OVX (20 days recovery) and a push-pull-cannula (PPC) implanted and stereotaxically aimed at the SCN region in the anterior hypothalamus. Following a 7-10 day recovery push-pull-perfusion (PPP) experiments were performed on either OVX females or on OVX females in which a silastic E2 implant (150 micrograms E2/ml. sesame oil), was placed sc 48 H prior to PPP. In other experiments progesterone (P4) was perfused in a pulsatile manner over the SCN region of the anterior hypothalamus. The overall average 5-HIAA release in the OVX treated rats (548 +/- 358 pg/10 min.) was similar to that in the OVX E2 group (694 +/- 148 pg/10 min). The average period of 5-HIAA release was (48.2 +/- 5.5 min) in the OVX group and (56.0 +/- 9.8 min) in the OVX E2 group. These results indicate that exposure of long term OVX rats (20 days) to E2 has no effect on the release or period of 5-HIAA release from serotonergic terminals concentrated in the SCN of the anterior hypothalamus.(ABSTRACT TRUNCATED AT 250 WORDS)

Issues in developing psychotherapy groups for preschool children in outpatient clinics.

A survey of 10 randomly selected clinics indicated that only 1 offered group psychotherapy for preschool children. Reasons given for the lack of such programs resembled the resistances encountered in the authors' clinic. The authors describe the solutions they found in creating and running therapy groups for preschool children and in integrating parent counseling with this treatment. It is suggested that professional groups provide in-service training opportunities in this area to counteract resistances resulting from clinic staffs' perceived lack of experience and expertise.