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Registro Completo |
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Biblioteca(s): |
Embrapa Caprinos e Ovinos. |
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Data corrente: |
22/06/2017 |
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Data da última atualização: |
22/06/2017 |
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Autoria: |
RODDA, C. P.; KUBOTA, M.; HEATH, J. A.; EBELING, P. R.; MOSELEY, J. M.; CARE, A. D.; CAPLE, I. W.; MARTIN, T. J. |
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Título: |
Evidence for a novel parathyroid hormone-related protein in fetal lamb parathyroid glands and sheep placenta: comparisons with a similar protein implicated in humoral hypercalcaemia of malignancy. |
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Ano de publicação: |
1988 |
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Fonte/Imprenta: |
Journal of Endocrinology, v. 117, n. 2, p. 261-272, May, 1988. |
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Idioma: |
Inglês |
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Conteúdo: |
Abstract: Parathyroid hormone (PTH)-like bioactivity, assayed as adenylate cyclase response in UMR 106-01 osteogenic sarcoma cells, was present in extracts of sheep fetal and maternal parathyroid glands and placenta. Preincubation of extracts with PTH(1-34) antiserum inhibited approximately 40% of the bioactivity in fetal parathyroid extracts, 50% in maternal parathyroid extracts, but only 10% of the bioactivity in the placental extract. Partial purification of placental extracts by chromatography yielded fractions containing PTH-like bioactivity which were similar in behaviour to that of PTH-related protein (PTHrP) from a human lung cancer cell line (BEN). An antiserum against synthetic PTHrP(1-16) partially inhibited the bioactivity of the placental extract and synthetic PTHrP(1-34), but had no effect on the bioactivity of bovine PTH(1-34) or bovine PTH(1-84). The placental PTH-like bioactivity was higher in mid- than in late gestation. Fetal parathyroid glands contained the highest PTH-like bioactivity. Thyroparathyroidectomy of one fetal twin lamb in each of 16 ewes between 110 and 125 days of gestation resulted in decreases of the plasma calcium concentration and reversal of the placental calcium gradient that existed between the ewe and the intact fetus. Perfusion of the placenta of each twin in anaesthetized ewes was carried out sequentially with autologous fetal blood in the absence of the exsanguinated fetus. The plasma calcium concentration in the blood perfusing the placenta of each twin increased, but reached a plateau at a lower concentration in the perfusing blood of thyroparathyroidectomized fetuses than in that of the intact fetuses. Addition of extracts of fetal parathyroid glands or of partially purified PTHrP resulted in further increases in plasma calcium in the autologous blood perfusing the placentae of thyroparathyroidectomized fetuses, but addition of bovine PTH(1-84) or rat PTH(1-34) had no effect. The presence of this PTH-like protein in the fetal parathyroid gland and placenta may contribute to the relative hypercalcaemia of the fetal lamb. This protein, which is similar to PTHrP associated with humoral hypercalcaemia of malignancy, stimulates the placental calcium pump responsible for maintaining a relative fetal hypercalcaemia during gestation. MenosAbstract: Parathyroid hormone (PTH)-like bioactivity, assayed as adenylate cyclase response in UMR 106-01 osteogenic sarcoma cells, was present in extracts of sheep fetal and maternal parathyroid glands and placenta. Preincubation of extracts with PTH(1-34) antiserum inhibited approximately 40% of the bioactivity in fetal parathyroid extracts, 50% in maternal parathyroid extracts, but only 10% of the bioactivity in the placental extract. Partial purification of placental extracts by chromatography yielded fractions containing PTH-like bioactivity which were similar in behaviour to that of PTH-related protein (PTHrP) from a human lung cancer cell line (BEN). An antiserum against synthetic PTHrP(1-16) partially inhibited the bioactivity of the placental extract and synthetic PTHrP(1-34), but had no effect on the bioactivity of bovine PTH(1-34) or bovine PTH(1-84). The placental PTH-like bioactivity was higher in mid- than in late gestation. Fetal parathyroid glands contained the highest PTH-like bioactivity. Thyroparathyroidectomy of one fetal twin lamb in each of 16 ewes between 110 and 125 days of gestation resulted in decreases of the plasma calcium concentration and reversal of the placental calcium gradient that existed between the ewe and the intact fetus. Perfusion of the placenta of each twin in anaesthetized ewes was carried out sequentially with autologous fetal blood in the absence of the exsanguinated fetus. The plasma calcium concentration in the blood perfusing t... Mostrar Tudo |
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Palavras-Chave: |
Fetal Proteins; Related Protein. |
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Thesagro: |
Placenta. |
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Thesaurus Nal: |
Metabolism; neoplasm proteins; parathyroid hormone; Pregnancy; Sheep. |
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Categoria do assunto: |
L Ciência Animal e Produtos de Origem Animal |
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Marc: |
LEADER 03232naa a2200301 a 4500
001 2071252
005 2017-06-22
008 1988 bl uuuu u00u1 u #d
100 1 $aRODDA, C. P.
245 $aEvidence for a novel parathyroid hormone-related protein in fetal lamb parathyroid glands and sheep placenta$bcomparisons with a similar protein implicated in humoral hypercalcaemia of malignancy.
260 $c1988
520 $aAbstract: Parathyroid hormone (PTH)-like bioactivity, assayed as adenylate cyclase response in UMR 106-01 osteogenic sarcoma cells, was present in extracts of sheep fetal and maternal parathyroid glands and placenta. Preincubation of extracts with PTH(1-34) antiserum inhibited approximately 40% of the bioactivity in fetal parathyroid extracts, 50% in maternal parathyroid extracts, but only 10% of the bioactivity in the placental extract. Partial purification of placental extracts by chromatography yielded fractions containing PTH-like bioactivity which were similar in behaviour to that of PTH-related protein (PTHrP) from a human lung cancer cell line (BEN). An antiserum against synthetic PTHrP(1-16) partially inhibited the bioactivity of the placental extract and synthetic PTHrP(1-34), but had no effect on the bioactivity of bovine PTH(1-34) or bovine PTH(1-84). The placental PTH-like bioactivity was higher in mid- than in late gestation. Fetal parathyroid glands contained the highest PTH-like bioactivity. Thyroparathyroidectomy of one fetal twin lamb in each of 16 ewes between 110 and 125 days of gestation resulted in decreases of the plasma calcium concentration and reversal of the placental calcium gradient that existed between the ewe and the intact fetus. Perfusion of the placenta of each twin in anaesthetized ewes was carried out sequentially with autologous fetal blood in the absence of the exsanguinated fetus. The plasma calcium concentration in the blood perfusing the placenta of each twin increased, but reached a plateau at a lower concentration in the perfusing blood of thyroparathyroidectomized fetuses than in that of the intact fetuses. Addition of extracts of fetal parathyroid glands or of partially purified PTHrP resulted in further increases in plasma calcium in the autologous blood perfusing the placentae of thyroparathyroidectomized fetuses, but addition of bovine PTH(1-84) or rat PTH(1-34) had no effect. The presence of this PTH-like protein in the fetal parathyroid gland and placenta may contribute to the relative hypercalcaemia of the fetal lamb. This protein, which is similar to PTHrP associated with humoral hypercalcaemia of malignancy, stimulates the placental calcium pump responsible for maintaining a relative fetal hypercalcaemia during gestation.
650 $aMetabolism
650 $aneoplasm proteins
650 $aparathyroid hormone
650 $aPregnancy
650 $aSheep
650 $aPlacenta
653 $aFetal Proteins
653 $aRelated Protein
700 1 $aKUBOTA, M.
700 1 $aHEATH, J. A.
700 1 $aEBELING, P. R.
700 1 $aMOSELEY, J. M.
700 1 $aCARE, A. D.
700 1 $aCAPLE, I. W.
700 1 $aMARTIN, T. J.
773 $tJournal of Endocrinology$gv. 117, n. 2, p. 261-272, May, 1988.
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Registro original: |
Embrapa Caprinos e Ovinos (CNPC) |
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