Registro Completo |
Biblioteca(s): |
Embrapa Caprinos e Ovinos. |
Data corrente: |
17/05/1996 |
Data da última atualização: |
17/05/1996 |
Autoria: |
KILE, J. P.; NETT, T. M. |
Título: |
Differential secretion of folicle-stimulating hormone and luteinizing hormone from ovine pituitary cells following activation of protein kinase A, protein kinase C, or increased intracellular cacium. |
Ano de publicação: |
1994 |
Fonte/Imprenta: |
Biology of Reproduction, v.50, n.1, p.49-54, 1994. |
Idioma: |
Inglês |
Conteúdo: |
A higher dose of GnRH is required to stimulate release of FSH than of LH, both in vivo and in vitro. Therefore, we tested the hypothesis that secretion of FSH may be mediated via a second messenger pathway different from the one that modulates secretion of LH. Pituitary cells from intact ewes were cultured in suspension in DMEM plus 10% wether serum. After 18 h, cell were washed and challenged for 2 h with agents capable of activating protein kinase A (dibutyryl cAMP), protein kinase C (phorbol 12-myristate 13-acetate; PMA), or increasing intracellular calcium (the calcium ionophore A23187). GnRH (0.01-10 DM) and PMA (0.2-20 nM) stimulated dose-dependent increases in secretion of LH. FSH secretion aIso was stimulated by GnRH and PMA; however, the percentage of total cellular FSH released was lower (p < 0.05) than the percentage of total cellular FSH released. Dibutyryl cAMP (10 mM) induced a modest release (p < 0.05) of both LH and FSH. A23187 (1-10 uM) stimulated secretion of LH in a dose-dependent manner but did not influence secretion of FSH; however, GnRH- and PMA-induced secretion of FSH required the presence of intracellular calcium. On the basis of the results of fuis study, we suggest that secretion of FSH is less than secretion of LH following direct activation of these second messenger systems. Furthermore, we suggest that in contrast to the situation for LH, increased intracellular calcium is not the primary stimulus for inducing secretion of FSH. |
Palavras-Chave: |
Regulacao Metabolica. |
Thesagro: |
Hipófise; Ovino; Reprodução. |
Categoria do assunto: |
-- |
Marc: |
LEADER 02099naa a2200181 a 4500 001 1516584 005 1996-05-17 008 1994 bl uuuu u00u1 u #d 100 1 $aKILE, J. P. 245 $aDifferential secretion of folicle-stimulating hormone and luteinizing hormone from ovine pituitary cells following activation of protein kinase A, protein kinase C, or increased intracellular cacium. 260 $c1994 520 $aA higher dose of GnRH is required to stimulate release of FSH than of LH, both in vivo and in vitro. Therefore, we tested the hypothesis that secretion of FSH may be mediated via a second messenger pathway different from the one that modulates secretion of LH. Pituitary cells from intact ewes were cultured in suspension in DMEM plus 10% wether serum. After 18 h, cell were washed and challenged for 2 h with agents capable of activating protein kinase A (dibutyryl cAMP), protein kinase C (phorbol 12-myristate 13-acetate; PMA), or increasing intracellular calcium (the calcium ionophore A23187). GnRH (0.01-10 DM) and PMA (0.2-20 nM) stimulated dose-dependent increases in secretion of LH. FSH secretion aIso was stimulated by GnRH and PMA; however, the percentage of total cellular FSH released was lower (p < 0.05) than the percentage of total cellular FSH released. Dibutyryl cAMP (10 mM) induced a modest release (p < 0.05) of both LH and FSH. A23187 (1-10 uM) stimulated secretion of LH in a dose-dependent manner but did not influence secretion of FSH; however, GnRH- and PMA-induced secretion of FSH required the presence of intracellular calcium. On the basis of the results of fuis study, we suggest that secretion of FSH is less than secretion of LH following direct activation of these second messenger systems. Furthermore, we suggest that in contrast to the situation for LH, increased intracellular calcium is not the primary stimulus for inducing secretion of FSH. 650 $aHipófise 650 $aOvino 650 $aReprodução 653 $aRegulacao Metabolica 700 1 $aNETT, T. M. 773 $tBiology of Reproduction$gv.50, n.1, p.49-54, 1994.
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Registro original: |
Embrapa Caprinos e Ovinos (CNPC) |
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