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Registro Completo |
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Biblioteca(s): |
Embrapa Caprinos e Ovinos. |
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Data corrente: |
01/08/1992 |
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Data da última atualização: |
21/06/2023 |
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Autoria: |
WAGNER, T. O. F.; ADAMS, T. E.; NETT. T. M. |
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Título: |
GNRH Interaction with anterior pituitary. I. Determination of the affinity and number of receptors for GNRH in ovine anterior pituitary. |
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Ano de publicação: |
1979 |
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Fonte/Imprenta: |
Biology of Reproduction, v. 20, n. 2, p. 140-149, 1979. |
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Idioma: |
Inglês |
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Conteúdo: |
Abstract: The specificity of the interaction of 152 [125I]-GNRH and its receptor in ovine anterior pituitary tissue was evaluated. Hormone and receptor were found to be stable during incubation for at least 4 h at 4°C in the presence of Aprotinin (100 KIU/ml). The association rate constant (k1) was 1.3 × 107 M−1 sec−1 and the dissociation rate (k−1) was 3 × 10−3 sec−1. Of the substances tested only synthetic GNRH and (D-Leu)6-(des-Gly-NH2)10-GNRH ethylamide were capable of inhibiting the binding of [125I]-GNRH to the anterior pituitary preparation. Vasopressin, melatonin, thyrotropin releasing hormone, LH, FSH, prolactin and inactive analogs of GNRH did not inhibit binding of [125I]-GNRH to its receptor. Scatchard plot analysis of saturation experiments indicated that a single class of high affinity sites (KA = 2.33 ± 0.31 × 1010 M−1) were present. It should be emphasized that the relative affinity of GNRH for receptors in anterior pituitary tissue is only 3% that of [125I]-GNRH. A constant concentration of available sites (4.85 ± 0.27 × 10−11 moles/g fresh anterior pituitary tissue) were present in ewes 10–12 days after superovulation. The number of receptors present in anterior pituitaries of anestrous ewes was not different at 0, 5, 10 or 20 h after injection of 100 µg estradiol-17β even though serum levels of LH increased ∼100-fold 13 h after treatment. |
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Thesagro: |
Fisiologia; Ovino; Reprodução. |
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Thesaurus Nal: |
Anterior pituitary hormones; Endocrinology; Gonadotropin-releasing hormone; Physiology; Reproduction; Sheep. |
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Categoria do assunto: |
L Ciência Animal e Produtos de Origem Animal |
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Marc: |
LEADER 02181naa a2200253 a 4500
001 1520011
005 2023-06-21
008 1979 bl uuuu u00u1 u #d
100 1 $aWAGNER, T. O. F.
245 $aGNRH Interaction with anterior pituitary. I. Determination of the affinity and number of receptors for GNRH in ovine anterior pituitary.$h[electronic resource]
260 $c1979
520 $aAbstract: The specificity of the interaction of 152 [125I]-GNRH and its receptor in ovine anterior pituitary tissue was evaluated. Hormone and receptor were found to be stable during incubation for at least 4 h at 4°C in the presence of Aprotinin (100 KIU/ml). The association rate constant (k1) was 1.3 × 107 M−1 sec−1 and the dissociation rate (k−1) was 3 × 10−3 sec−1. Of the substances tested only synthetic GNRH and (D-Leu)6-(des-Gly-NH2)10-GNRH ethylamide were capable of inhibiting the binding of [125I]-GNRH to the anterior pituitary preparation. Vasopressin, melatonin, thyrotropin releasing hormone, LH, FSH, prolactin and inactive analogs of GNRH did not inhibit binding of [125I]-GNRH to its receptor. Scatchard plot analysis of saturation experiments indicated that a single class of high affinity sites (KA = 2.33 ± 0.31 × 1010 M−1) were present. It should be emphasized that the relative affinity of GNRH for receptors in anterior pituitary tissue is only 3% that of [125I]-GNRH. A constant concentration of available sites (4.85 ± 0.27 × 10−11 moles/g fresh anterior pituitary tissue) were present in ewes 10–12 days after superovulation. The number of receptors present in anterior pituitaries of anestrous ewes was not different at 0, 5, 10 or 20 h after injection of 100 µg estradiol-17β even though serum levels of LH increased ∼100-fold 13 h after treatment.
650 $aAnterior pituitary hormones
650 $aEndocrinology
650 $aGonadotropin-releasing hormone
650 $aPhysiology
650 $aReproduction
650 $aSheep
650 $aFisiologia
650 $aOvino
650 $aReprodução
700 1 $aADAMS, T. E.
700 1 $aNETT. T. M.
773 $tBiology of Reproduction$gv. 20, n. 2, p. 140-149, 1979.
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Registro original: |
Embrapa Caprinos e Ovinos (CNPC) |
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