Attenuation of the magnitude of suckling-induced prolactin release with advancing lactation: mechanisms.
Attenuation of the magnitude of suckling-induced prolactin release with advancing lactation: mechanisms.
复制标题
哺乳诱导的催乳素释放量随泌乳提前而减弱：机制。
DOI：
10.1016/0024-3205(94)00920-1
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发表时间：
1995
期刊：
影响因子：
6.1
通讯作者：
Moghissi,KS
中科院分区：
文献类型：
--
作者：
Shanti,AS;Subramanian,MG;Savoy-Moore,RT;Kruger,ML;Moghissi,KS
为了研究为什么哺乳诱导的血浆催乳素水平会随着泌乳的推进而下降，我们检测了哺乳期大鼠在哺乳和哺乳早期、中期和后期的药物操作后的催乳素释放。哺乳第2天，调整窝数至8只。第3天置入心房导管，于泌乳第5、11、17天进行实验。为了检测哺乳诱导的催乳素释放情况，在0800 h取出幼犬，1100 h将延长管连接到导管上，1200 h将幼犬送回母池。分别在哺乳开始前、开始后10、30、60、90和120 min采集血样。研究了泌乳大鼠对舒必利和促甲状腺激素释放激素（TRH）的反应。分别于舒必利预处理大鼠（10或40 μg/kg BW）前、10、30、60和90 min及TRH后5、10、20和30 min（1或4 μg/kg BW）采血。泌乳素释放反应，服用舒必利或舒必利和TRH随着泌乳的进展而减少。根据这些结果，我们得出结论，垂体前叶对催乳素释放刺激的难耐性至少是哺乳诱导的催乳素释放随着泌乳的推进而下降的部分原因。
To study why suckling-induced plasma prolactin levels decline in magnitude with advancing lactation, we examined prolactin release in lactating rats following suckling and pharmacologic manipulations during early, mid- and late lactation. On day 2 of lactation, litters were adjusted to 8 pups. On day 3, dams were implanted with an atrial catheter and experiments were conducted on lactation days 5, 11 and 17. To examine suckling-induced prolactin release, pups were removed at 0800 h, an extension was attached to the catheter at 1100 h, and pups returned to dams at 1200 h. Blood samples were obtained before, and at 10, 30, 60, 90 and 120 min after suckling started. Prolactin responses to sulpiride and thyrotropin releasing hormone (TRH) administration were studied in lactating rats separated from their litters for 4 hours. Blood samples were obtained before, and at 10, 30, 60 and 90 min after sulpiride (10 or 40 μg/kg BW) and 5, 10, 20 and 30 min after TRH (1 or 4 μg/kg BW) in rats pretreated with sulpiride. Prolactin release in response to suckling, administration of sulpiride or sulpiride and TRH diminished as lactation advanced. From these results, we conclude that refractoriness in anterior pituitary lactrotropes to prolactin-releasing stimuli is at least partially responsible for the decline in suckling-induced prolactin release with advancing lactation.