Orstead K M, Blask D E
Neuroendocrinology. 1987 Mar;45(3):182-90. doi: 10.1159/000124723.
The purpose of this investigation was to elucidate the differences in the nature and time course of changes in in vitro prolactin (PRL) cell activity between blinded and blind/pinealectomized female hamsters. Adult female golden hamsters were either left intact, blinded and sham-pinealectomized (Blind/Sham) or blinded and pinealectomized (Blind/Pinx). Twelve weeks after surgeries, animals were killed by decapitation and randomized hemipituitaries were incubated for a total of either 30, 60, 90, 120, 180 or 240 min. PRL release in vivo, as estimated by monitoring serum titers of immunoreactive PRL (IR-PRL), was markedly reduced in Blind/Sham animals; pinealectomy completely prevented this depression. PRL storage was assessed by measuring total levels (i.e., medium + pituitaries) of IR-PRL in vitro. Total, pituitary and media values of IR-PRL were all significantly depressed in Blind/Sham females. Pinealectomy of blinded animals almost completely prevented these reductions. PRL synthesis, as evaluated by measuring the amount of 3H-leucine incorporated into PRL in vitro, was profoundly reduced in Blind/Sham females. Surprisingly, pinealectomy failed to prevent the blinding-induced decrease in PRL production. From these data, we conclude that in the light-deprived female hamster the pineal gland inhibits PRL storage and release, while the depression in PRL synthesis may be independent of a pineal influence.
本研究的目的是阐明雌性仓鼠在致盲和致盲/松果体切除后，体外催乳素（PRL）细胞活性变化的性质和时间进程上的差异。成年雌性金黄仓鼠被分为三组：完整对照组、致盲并假松果体切除组（致盲/假手术组）、致盲并松果体切除组（致盲/松果体切除组）。手术后12周，动物断头处死，随机选取半脑垂体孵育30、60、90、120、180或240分钟。通过监测免疫反应性PRL（IR-PRL）的血清滴度估计体内PRL释放，结果显示致盲/假手术组动物的PRL释放显著降低；松果体切除完全阻止了这种抑制。通过测量体外IR-PRL的总水平（即培养基+垂体）评估PRL储存。致盲/假手术组雌性动物的IR-PRL总水平、垂体水平和培养基水平均显著降低。致盲动物的松果体切除几乎完全阻止了这些降低。通过测量体外掺入PRL中的3H-亮氨酸量评估PRL合成，结果显示致盲/假手术组雌性动物的PRL合成显著降低。令人惊讶的是，松果体切除未能阻止致盲引起的PRL产生减少。根据这些数据，我们得出结论，在光剥夺的雌性仓鼠中，松果体抑制PRL储存和释放，而PRL合成的降低可能与松果体影响无关。
