The endothelin-A receptor subtype transduces the effects of the endothelins in the anterior pituitary gland.
All members of the mammalian endothelin family of peptides exert significant effects on prolactin and luteinizing hormone release from dispersed anterior pituitary cells in vitro. The rank order of potency for the prolactin inhibiting effects of the endothelins is ET-1 = ET-2 much less than ET-3. This suggests an involvement of the ET-A receptor subtype. The selective ET-A receptor antagonist BQ-123 antagonized the effects of the ETs in a competitive fashion with pA2 values of 6.1 (ET-1), 5.7 (ET-2) and 6.4 (ET-3), when added simultaneously with the ETs. This suggests the involvement of the ET-A receptor subtype in the actions of the ETs within the anterior pituitary gland.
Samson
W K
WK
Department of Physiology, University of North Dakota School of Medicine, Grand Forks 58202.
D000818:Animals; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D016232:Endothelins / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D007986:Luteinizing Hormone / Q000378:metabolism; D010456:Peptides, Cyclic / Q000494:pharmacology; D010903:Pituitary Gland, Anterior / Q000378:metabolism*; D011388:Prolactin / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000037:antagonists & inhibitors / Q000502:physiology*; D017466:Receptors, Endothelin; D015398:Signal Transduction / Q000502:physiology*
D016232:Endothelins; D010456:Peptides, Cyclic; D011956:Receptors, Cell Surface; D017466:Receptors, Endothelin; D011388:Prolactin; D007986:Luteinizing Hormone; C072247:cyclo(Trp-Asp-Pro-Val-Leu)