Role of pup age, estradiol-17 beta and pituitary responsiveness in the differences in the suckling-induced prolactin response during early and late lactation.
Role of pup age, estradiol-17 beta and pituitary responsiveness in the differences in the suckling-induced prolactin response during early and late lactation.
复制标题
幼犬年龄、雌二醇-17β和垂体反应性在哺乳早期和晚期哺乳诱导的催乳素反应差异中的作用。
DOI：
10.1095/biolreprod29.2.400
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发表时间：
1983
影响因子：
3.6
通讯作者：
Selmanoff,C
中科院分区：
文献类型：
--
作者：
Selmanoff,M;Selmanoff,C
在产后10天和20天的雌性大鼠中研究了哺乳诱导的催乳素（Prl）反应。在产后20天的母亲的反应有一个较慢的开始，有显着降低峰值和恢复到基线比产后10天的母亲的反应稍早。哺乳后期的迟钝反应，看到在哺乳30分钟的母亲，并保持在一个较长的时间间隔在母亲连续哺乳120分钟。这种难治性的现象是不是由于降低哺乳强度提供的20天相对于10天大的幼崽。垂体泌乳素释放反应促甲状腺激素释放激素（TRH）和氟哌啶醇的挑战也没有区分产后10天和20天的母亲。与产后10天的母亲相比，产后20天的母亲雌二醇-17 β水平显著较高，这一发现不能解释反应迟钝。幼犬从产后10天的母亲分离4，24，48或72小时并没有产生钝化的反应，如在哺乳后期看到的。这表明，下丘脑机制介导的哺乳诱导的PRL释放成为难治性的哺乳刺激在断奶前期间。
The suckling-induced prolactin (Prl) response was studied in 10- and 20-day postpartum female rats. The response in 20-day postpartum mothers has a slower onset, has markedly reduced peak values and returns to baseline somewhat sooner than the response in 10-day postpartum mothers. The blunted response of late lactation was seen in mothers suckled for 30 min and was maintained over a longer interval in mothers continuously suckled for 120 min. This refractory phenomenon was not due to decreased suckling intensity provided by 20-day relative to 10-day-old pups. Pituitary gland Prl release in response to thyrotropin releasing hormone (TRH) and haloperidol challenges also did not distinguish 10- from 20-day postpartum mothers. Significantly higher estradiol-17βlevels were found in 20-day compared with 10-day postpartum mothers, a finding which cannot account for the blunted response. Pup separation from 10-day postpartum mothers for 4, 24, 48 or 72 h did not produce a blunted response like that seen in late lactation. It is suggested that the hypothalamic mechanism mediating suckling-induced Prl release becomes refractory to the suckling stimulus during the preweaning period.