Data/hora: 11/06/2024 20:45:47

Biblioteca(s): | Embrapa Caprinos e Ovinos.
Data corrente: | 16/10/2002
Data da última atualização: | 16/10/2002
Autoria: | TSAI, S. J.; ANDERSON, L. E.; JUENGEL, J.; NISWENDER, G. D.; WILTBANK, M. C.
Título: | Regulation of prostaglandin F2alpha and E receptor mRNA by prostaglandin F2alpha in ovine corpora lutea.
Ano de publicação: | 1998
Fonte/Imprenta: | Journal of Reproduction and Fertility, v. 114, n. 1, p. 69-75, 1998.
Idioma: | Inglês
Conteúdo: | Prostaglandins regulate many physiological functions, including reproduction, by binding to specific plasma membrane receptors. In this study we evaluated the regulation of PGF 2alpha (FP) and PGE (EP 3 subtype) receptors in ovine corpora lutea. In the first study, tissue distribution of FP and EP 3 receptors was evaluated in 13 ovine tissues.  FP receptor rnRNA was present in 100-fold higher concentration in corpora lutea than in other tissues. Similarly, [3H]PGF2alpha binding was much greater in luteal plasma membranes than in membranes from other tissues. In contrast, EP 3 receptor rnRNA was more uniformly distributed, with high concentrations in adrenal medulla, inner myometrium, kidney medulla and heart. The distribution of [3H]PGE1 binding was generally similar to EP 3 rnRNA, with the exception that ovarian stroma, endometrium and outer myometrium had high [3H]PGE1 binding but low concentrations of EP 3 receptor mRNA. The second study evaluated the action of PGF2" on luteal rnRNA encoding FP and EP 3 receptors. Ewes had PGF 2alpha or saline infused into the ovarian artery and corpora lutea were removed at O, 1,4, 12 and 24 h. FP receptor mRNA decreased by 50% at 12 and 24 h after infusion with PGF 2alpha whereas EP 3 rnRNA was unchanged. Treatment of large luteal cells with PGF2alpha' phorbol didecanoate (protein kinase C activator), or ionomycin (calcium ionophore) decreased FP receptor rnRNA after 24 h  (P < 0.05). Glyceraldehyde 3-phosphate dehydrogenase rnRNA was not changed by any treatment. These results show that EP3 receptors are expressed in many tissues and  expression is not regulated by PGF 2alpha. In contrast, FP receptors are primarily expressed in corpora lutea and expression is inhibited by PGF 2alpha.
Thesagro: | Corpo Lúteo; Ovino; Prostaglandina.
Categoria do assunto: | --
Registro original: | Embrapa Caprinos e Ovinos (CNPC)
Exemplares: | CNPC - (14978-1) - ADC - AP - -- -  -  - v.114, n.1 - DIS