Dopamine in hypophysial portal blood: relationship to circulating prolactin in pregnant and lactating rats.
Dopamine in hypophysial portal blood: relationship to circulating prolactin in pregnant and lactating rats.
复制标题
垂体门静脉血中的多巴胺：与妊娠和哺乳大鼠循环催乳素的关系。
作者：
N. Ben;Mary Ann Neill;L. Arbogast;L. Peters;M. T. Hoefer
本文研究了妊娠期和哺乳期垂体门脉血中多巴胺(DA)浓度与外周血中催乳素(PRL)浓度的关系。断头采集的血浆PRL水平在妊娠18-21天较低，在22天升高，在哺乳前10天一直保持较高水平。母鼠和仔鼠分离24小时后，血浆催乳素浓度显著降低。在所有大鼠中，门脉DA含量均高于动脉血浆，而去甲肾上腺素和肾上腺素的含量均高于动脉血浆。妊娠18~21日龄大鼠门静脉血浆DA水平为4.9±0.7 ng/ml，显著高于哺乳期1~5天和6~10日龄大鼠门静脉血浆DA水平(分别为2.9±0.3和2.7±0.4 ng/ml)。与分离30分钟相比，分离24小时的母鼠和仔鼠门静脉血浆中的多巴胺显著升高。下丘脑、垂体前叶或垂体后叶的儿茶酚胺浓度无明显差异。
The relationship between dopamine (DA) concentration in hypophysial portal blood and that of PRL in systemic blood during gestation and lactation was investigated. PRL level in plasma collected by decapitation was low during the 18–21 days of gestation, increased on day 22, and remained elevated throughout the first 10 days of lactation. Separation of mothers from pups for 24 h resulted in a marked reduction in plasma PRL concentration. DA, but not norepinephrine or epinephrine, was higher in portal than in arterial plasma in all rats. DA in portal plasma of 18- to 21-day pregnant rats [4.9 ± 0.7 ng/ ml, (mean ± SEM)] was significantly higher than that in portal plasma from 1- to 5- and 6- to 10-day lactating rats (2.9 ± 0.3 and 2.7 ± 0.4 ng/ml, respectively). Separation of mothers from pups for 24 h resulted in a significant elevation of portal plasma dopamine compared with separation for 30 min. No differences were found in hypothalamic, anterior, or posterior pituitary catecholamine concentrations as a...