Central administration of 8-OH-DPAT and mCPP stimulates prolactin secretion in ovariectomized, estrogen-treated rats: lack of an effect on tuberoinfundibular dopaminergic neuron activity.
The effects of central administration of two serotonin receptor agonists, 8-OH-DPAT and mCPP, on tuberoinfundibular dopaminergic (TIDA) neuron activity and serum prolactin (PRL) levels in ovariectomized, estrogen-treated rats were determined. 8-OH-DPAT dose-dependently (0.1-10 microgram/rat, icv) stimulated serum PRL levels, and depressed serotonergic neuron activity in 30 min. However, the TIDA neuron activity was not affected at all. Similar treatment of mCPP was less effective than 8-OH-DPAT: only the highest dose of mCPP (10 microgram) stimulated PRL secretion and inhibited serotonergic neuron activity. No change in TIDA neuron activity was observed either. We conclude that central serotonin acts on 5-HT1 receptors to stimulate the PRL secretion, which may not involve the TIDA neurons.
Pan
J T
JT
Department of Physiology, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
Yang
I C
IC
D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology*; D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000187:drug effects* / Q000502:physiology; D004298:Dopamine / Q000378:metabolism / Q000502:physiology*; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology; D045166:Estradiol Congeners / Q000494:pharmacology*; D005260:Female; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D007276:Injections, Intraventricular; D009474:Neurons / Q000187:drug effects* / Q000502:physiology; D010052:Ovariectomy; D010879:Piperazines / Q000494:pharmacology*; D011388:Prolactin / Q000378:metabolism*; D011863:Radioimmunoassay; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000378:metabolism; D017366:Serotonin Receptor Agonists / Q000494:pharmacology*; D013268:Stimulation, Chemical
D045166:Estradiol Congeners; D010879:Piperazines; D017366:Serotonin Receptor Agonists; D015102:3,4-Dihydroxyphenylacetic Acid; D012701:Serotonin; D004958:Estradiol; D006897:Hydroxyindoleacetic Acid; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D011388:Prolactin; C008958:polyestradiol phosphate; C015068:1-(3-chlorophenyl)piperazine; D004298:Dopamine