Registro Completo |
Biblioteca(s): |
Embrapa Caprinos e Ovinos. |
Data corrente: |
22/06/2017 |
Data da última atualização: |
22/06/2017 |
Autoria: |
THOMAS, G. B.; CUMMINS, J. T.; SMYTHE, G. A.; GLEESON, R. M.; DOW, R. C.; FINK, G. |
Título: |
Concentrations of dopamine and noradrenaline in hypophysial portal blood in the sheep and the rat. |
Ano de publicação: |
1989 |
Fonte/Imprenta: |
Journal of Endocrinology, v. 121, n. 1, p. 141-148, Apr. 1989. |
DOI: |
10.1677/joe.0.1210141 |
Idioma: |
Inglês |
Conteúdo: |
Abstract: The concentrations of dopamine, noradrenaline and their respective primary neuronal metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and 3,4-dihydroxyphenylethyleneglycol (DHPG) were measured in the hypophysial portal and peripheral plasma of sheep and rats by combined gas chromatography-mass spectrometry. Hypophysial portal and jugular blood samples were taken at 5- to 10-min intervals for 3-7 h from six conscious ovariectomized ewes. Blood was also collected for 30 min under urethane anaesthesia from the cut pituitary stalk from 16 pro-oestrous female and five intact male rats. In ovariectomized ewes, noradrenaline concentrations were higher in hypophysial portal plasma than in peripheral plasma (6.6 +/- 0.8 vs 2.2 +/- 0.4 nmol/l). In contrast, dopamine was undetectable (less than 1 nmol/l) in the portal and peripheral plasma of all ewes. Plasma levels of DOPAC and DHPG in portal and jugular samples were similar. In all pro-oestrous female rats, plasma concentrations of dopamine were higher in portal blood than in jugular blood (8.0 +/- 1.4 vs 4.8 +/- 0.6 nmol/l). Detectable concentrations of dopamine were measured in the portal plasma of two out of five male rats. Noradrenaline concentrations were higher in portal plasma than in peripheral plasma of both female (8.3 +/- 1.7 vs 3.7 +/- 0.6 nmol/l) and male (14.8 +/- 2.7 vs 6.1 +/- 1.2 nmol/l) rats. These data show that noradrenaline, but not dopamine, is secreted into the long portal vessels in sheep. The results suggest that there are species differences in the secretion of hypothalamic dopamine into hypophysial portal blood. MenosAbstract: The concentrations of dopamine, noradrenaline and their respective primary neuronal metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and 3,4-dihydroxyphenylethyleneglycol (DHPG) were measured in the hypophysial portal and peripheral plasma of sheep and rats by combined gas chromatography-mass spectrometry. Hypophysial portal and jugular blood samples were taken at 5- to 10-min intervals for 3-7 h from six conscious ovariectomized ewes. Blood was also collected for 30 min under urethane anaesthesia from the cut pituitary stalk from 16 pro-oestrous female and five intact male rats. In ovariectomized ewes, noradrenaline concentrations were higher in hypophysial portal plasma than in peripheral plasma (6.6 +/- 0.8 vs 2.2 +/- 0.4 nmol/l). In contrast, dopamine was undetectable (less than 1 nmol/l) in the portal and peripheral plasma of all ewes. Plasma levels of DOPAC and DHPG in portal and jugular samples were similar. In all pro-oestrous female rats, plasma concentrations of dopamine were higher in portal blood than in jugular blood (8.0 +/- 1.4 vs 4.8 +/- 0.6 nmol/l). Detectable concentrations of dopamine were measured in the portal plasma of two out of five male rats. Noradrenaline concentrations were higher in portal plasma than in peripheral plasma of both female (8.3 +/- 1.7 vs 3.7 +/- 0.6 nmol/l) and male (14.8 +/- 2.7 vs 6.1 +/- 1.2 nmol/l) rats. These data show that noradrenaline, but not dopamine, is secreted into the long portal vessels in sheep. The resul... Mostrar Tudo |
Palavras-Chave: |
Dihydroxyphenylethylene glycol; Inbred Strains; Regional Blood Flow. |
Thesaurus Nal: |
Blood; dopamine; Ewes; norepinephrine; rats; Sheep. |
Categoria do assunto: |
L Ciência Animal e Produtos de Origem Animal |
Marc: |
LEADER 02444naa a2200301 a 4500 001 2071305 005 2017-06-22 008 1989 bl uuuu u00u1 u #d 024 7 $a10.1677/joe.0.1210141$2DOI 100 1 $aTHOMAS, G. B. 245 $aConcentrations of dopamine and noradrenaline in hypophysial portal blood in the sheep and the rat. 260 $c1989 520 $aAbstract: The concentrations of dopamine, noradrenaline and their respective primary neuronal metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and 3,4-dihydroxyphenylethyleneglycol (DHPG) were measured in the hypophysial portal and peripheral plasma of sheep and rats by combined gas chromatography-mass spectrometry. Hypophysial portal and jugular blood samples were taken at 5- to 10-min intervals for 3-7 h from six conscious ovariectomized ewes. Blood was also collected for 30 min under urethane anaesthesia from the cut pituitary stalk from 16 pro-oestrous female and five intact male rats. In ovariectomized ewes, noradrenaline concentrations were higher in hypophysial portal plasma than in peripheral plasma (6.6 +/- 0.8 vs 2.2 +/- 0.4 nmol/l). In contrast, dopamine was undetectable (less than 1 nmol/l) in the portal and peripheral plasma of all ewes. Plasma levels of DOPAC and DHPG in portal and jugular samples were similar. In all pro-oestrous female rats, plasma concentrations of dopamine were higher in portal blood than in jugular blood (8.0 +/- 1.4 vs 4.8 +/- 0.6 nmol/l). Detectable concentrations of dopamine were measured in the portal plasma of two out of five male rats. Noradrenaline concentrations were higher in portal plasma than in peripheral plasma of both female (8.3 +/- 1.7 vs 3.7 +/- 0.6 nmol/l) and male (14.8 +/- 2.7 vs 6.1 +/- 1.2 nmol/l) rats. These data show that noradrenaline, but not dopamine, is secreted into the long portal vessels in sheep. The results suggest that there are species differences in the secretion of hypothalamic dopamine into hypophysial portal blood. 650 $aBlood 650 $adopamine 650 $aEwes 650 $anorepinephrine 650 $arats 650 $aSheep 653 $aDihydroxyphenylethylene glycol 653 $aInbred Strains 653 $aRegional Blood Flow 700 1 $aCUMMINS, J. T. 700 1 $aSMYTHE, G. A. 700 1 $aGLEESON, R. M. 700 1 $aDOW, R. C. 700 1 $aFINK, G. 773 $tJournal of Endocrinology$gv. 121, n. 1, p. 141-148, Apr. 1989.
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Embrapa Caprinos e Ovinos (CNPC) |
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