Circadian variations in plasma growth hormone and prolactin in the infant rat: comparison with the adult pattern.
Circadian variations in plasma growth hormone and prolactin in the infant rat: comparison with the adult pattern.
复制标题
幼鼠血浆生长激素和催乳素的昼夜变化：与成年模式的比较。
DOI：
10.1016/0024-3205(76)90310-6
复制
发表时间：
1976
期刊：
影响因子：
6.1
通讯作者：
E. Müller
中科院分区：
文献类型：
--
作者：
D. Cocchi;I. Gil;A. Panerai;V. Locatelli;E. Müller
在受控的24小时光暗周期中，每隔3小时测定10日龄雄性和雌性大鼠的血浆生长激素（GH）和催乳素（PRL）水平；平行测定脑单胺（MA’s）、多巴胺（DA）、去甲肾上腺素（NE）和血清素（5-HT）浓度。将婴儿大鼠血浆GH、PRL和脑MA水平与50日龄雄性大鼠24小时周期内的相同测定结果进行比较。生长激素水平在幼鼠血浆中相当均匀，不显示昼夜周期性，而PRL水平在下午晚些时候显示昼夜激增（1800）。在成年大鼠中，生长激素水平在24小时周期内表现出广泛的波动，没有昼夜周期性，而PRL水平在一天（1500-1800）和一个夜间（2400）激增。在2小时间隔15分钟取样的成年大鼠中发现搏动性GH分泌，这似乎在幼鼠中缺乏。在幼龄大鼠的大脑中，DA和NE的水平表现出与成年大鼠大脑相似的昼夜节律模式，而5-羟色胺的水平则没有昼夜节律变化。
Radioimmunoassayable (RIA) plasma growth hormone (GH) and prolactin (PRL) levels were determined at 3 hr intervals during a controlled 24-hr light-dark cycle in 10-day-old male and female rats; parallel measurements were made of brain monoamines (MA's), dopamine (DA), norepinephrine (NE) and serotonin (5-HT) concentration. Plasma GH and PRL and brain MA levels found in infant rats were compared to the same determinations made during the 24-hr cycle in 50-day-old male rats. GH levels were rather uniform and did not show circadian periodicity in the plasma of infant rats, while PRL levels showed a diurnal surge in the late afternoon hr (1800). In adult rats, GH levels exhibited wide fluctuations during the 24-hr cycle and no circadian periodicity, while PRL levels showed one diurnal (1500–1800) and one nocturnal (2400) surge. A pulsatile GH secretion was found in adult rats sampled at 15 min intervals over a period of 2 hr, which seemed to be lacking in infant rats. In the brain of infant rats, DA and NE levels exhibited circadian patterns which resembled the ones present in the brain of adult rats, whereas no circadian variations were present in 5-HT levels.