We have used the nonpeptide angiotensin II (ANG II) receptor antagonists losartan (receptor subtype AT1) and PD-123319 (AT2) to determine the participation of ANG II receptor subtypes in luteinizing hormone-releasing hormone (LHRH)-induced prolactin release in a perifusion study using intact pituitaries in vitro. LHRH (1.85 x 10-7 M) released prolactin consistently, whereas losartan (10-5 M) abolished prolactin response without modifying basal prolactin or luteinizing hormone (LH) and follicle-stimulating hormone (FSH) release. PD-123319 (10-5 M) had no effect on basal or LHRH-induced prolactin, LH, or FSH release. We also determined that the effect of ANG II on prolactin release was mediated by the same receptor subtype. In adenohypophysial cells dispersed in vitro ANG II (10-8 M) released prolactin. Losartan (10-7 and 10-6 M), but not PD-123319, inhibited this effect. We conclude that in intact hypophyses of 15-day-old female rats the effect of LHRH on prolactin release is readily demonstrated. LHRH-induced prolactin release appears to be mediated by ANG II acting in a paracrine manner on AT1 receptors located on lactotrophs.
Documento: | Artículo |
Título: | Effects of LHRH and ANG II on prolactin stimulation are mediated by hypophysial AT1 receptor subtype |
Autor: | Becu-Villalobos, D.; Lacau-Mengido, I.M.; Thyssen, S.M.; Diaz-Torga, G.S.; Libertun, C. |
Filiación: | Laboratorio de Neuroendocrinologia, IBME, CONICET, V. Obligado 2490, 1428 Buenos Aires, Argentina |
Palabras clave: | angiotensin II receptor subtypes; losartan; luteinizing hormone-releasing hormone; paracrine; PD-123319; pituitary; 1 (4 dimethylamino 3 methylbenzyl) 5 diphenylacetyl 4,5,6,7 tetrahydro 1h imidazo[4,5 c]pyridine 6 carboxylic acid; angiotensin; angiotensin receptor; follitropin; gonadorelin; losartan; losartan potassium; luteinizing hormone; prolactin; receptor subtype; adenohypophysis; animal cell; animal tissue; article; controlled study; female; follitropin release; luteinizing hormone release; nonhuman; priority journal; prolactin release; prolactin secreting cell; rat; Angiotensin II; Animal; Biphenyl Compounds; Female; Gonadorelin; Imidazoles; In Vitro; Losartan; Perfusion; Pituitary Gland; Prolactin; Pyridines; Rats; Rats, Sprague-Dawley; Receptors, Angiotensin; Support, Non-U.S. Gov't; Tetrazoles |
Año: | 1994 |
Volumen: | 266 |
Número: | 2 29-2 |
Página de inicio: | E274 |
Página de fin: | E278 |
Título revista: | American Journal of Physiology - Endocrinology and Metabolism |
Título revista abreviado: | AM. J. PHYSIOL. ENDOCRINOL. METAB. |
ISSN: | 00029513 |
CODEN: | AJPMD |
CAS: | 1 (4 dimethylamino 3 methylbenzyl) 5 diphenylacetyl 4,5,6,7 tetrahydro 1h imidazo[4,5 c]pyridine 6 carboxylic acid, 130663-39-7; angiotensin, 11128-99-7, 1407-47-2; follitropin, 9002-68-0; gonadorelin, 33515-09-2, 9034-40-6; losartan potassium, 124750-99-8; losartan, 114798-26-4; luteinizing hormone, 39341-83-8, 9002-67-9; prolactin, 12585-34-1, 50647-00-2, 9002-62-4; Angiotensin II, 11128-99-7; Biphenyl Compounds; Gonadorelin, 33515-09-2; Imidazoles; Losartan, 114798-26-4; PD 123319, 130663-39-7; Prolactin, 9002-62-4; Pyridines; Receptors, Angiotensin; Tetrazoles |
Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00029513_v266_n229-2_pE274_BecuVillalobos |