Pulsatile gonadotropin secretion and basal prolactin levels during dopamine D-1 receptor stimulation in normal women.
The effect of the specific dopamine D-1 receptor agonist Fenoldopam on pulsatile gonadotropin secretion and prolactin (PRL) secretion was investigated in normal women. The gonadotropin response to subsequent gonadotropin-releasing-hormone (GnRH) administration was also studied. Eight women received 8-hour infusions of either Fenoldopam (0.5 microgram/kg per minute) (Smith Kline and French, Harrow, United Kingdom) or placebo. After 7 hours of infusion, GnRH was given intravenously. The luteinizing hormone (LH) response to GnRH was significantly higher during Fenoldopam compared with placebo (LH; 13.1 +/- 9.0 versus 9.4 +/- 4.3 IU/L). Basal LH levels, pulse amplitude, and pulse frequency during Fenoldopam infusion were not different from placebo. Prolactin levels increased significantly during Fenoldopam (24 +/- 2 micrograms/L) compared with placebo (16 +/- 2). The results suggest that D-1 receptor stimulation does not affect pulsatile gonadotropin secretion but increases the pituitary responsiveness to GnRH. Additionally, dopamine and Fenoldopam have opposite effects on PRL secretion, the latter increasing PRL levels.
Boesgaard
S
S
Department of Internal Medicine and Endocrinology, Herlev Hospital, University of Copenhagen, Denmark.
Hagen
C
C
Hangaard
J
J
Andersen
A N
AN
Eldrup
E
E
D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D000328:Adult; D003346:Corticotropin-Releasing Hormone / Q000494:pharmacology; D015259:Dopamine Agents / Q000494:pharmacology*; D004958:Estradiol / Q000097:blood; D005260:Female; D018818:Fenoldopam; D005640:Follicle Stimulating Hormone / Q000097:blood; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology; D006801:Humans; D007262:Infusions, Intravenous; D007986:Luteinizing Hormone / Q000097:blood / Q000378:metabolism*; D011388:Prolactin / Q000097:blood / Q000378:metabolism*; D011954:Receptors, Dopamine / Q000187:drug effects / Q000502:physiology*; D017447:Receptors, Dopamine D1; D012016:Reference Values; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology; D013997:Time Factors
D015259:Dopamine Agents; D011954:Receptors, Dopamine; D017447:Receptors, Dopamine D1; D007987:Gonadotropin-Releasing Hormone; D004958:Estradiol; D013973:Thyrotropin-Releasing Hormone; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D011388:Prolactin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D003346:Corticotropin-Releasing Hormone; D018818:Fenoldopam