Caligaris L, Taleisnik S
Neuroendocrinology. 1977;23(6):323-9. doi: 10.1159/000122681.
Serum prolactin (Prl) concentrations in ovariectomized rats were low without significant differences between morning and afternoon values. These levels were not affected by either frontal or caudal hypothalamic deafferentation. However, they increased after lesioning the hypothalamic median eminence (ME). Three days after the injection of 20 microgram estradiol benzoate (EB) into ovariectomized non-lesioned rats, a rise in serum Prl occurred in the afternoon but not in the morning. In animals with ME lesions estrogen enhanced both morning and afternoon values. The animals with caudal hypothalamic deafferentation and those which had undergone sham operation showed the same pattern as the normal animals. On the contrary, after estrogen treatment of rats with frontal hypothalamic deafferentation high serum Prl concentration during the morning and low levels in the afternoon were observed. It is concluded that estrogen effects on Prl secretion are in part mediated by frontal neural afferents to the hypothalamus. They would facilitate Prl inhibiting factor (PIF) secretion in the morning and inhibit PIF secretion in the afternoon.
去卵巢大鼠的血清催乳素（Prl）浓度较低，上午和下午的值之间无显著差异。这些水平不受下丘脑前部或尾部去传入神经支配的影响。然而，在下丘脑正中隆起（ME）受损后，它们会升高。在去卵巢未受损大鼠中注射20微克苯甲酸雌二醇（EB）三天后，血清Prl在下午升高，但上午未升高。在ME受损的动物中，雌激素使上午和下午的值均升高。下丘脑尾部去传入神经支配的动物和接受假手术的动物表现出与正常动物相同的模式。相反，在用雌激素治疗下丘脑前部去传入神经支配的大鼠后，观察到上午血清Prl浓度高而下午水平低。结论是雌激素对Prl分泌的影响部分由下丘脑的前部神经传入介导。它们会在上午促进催乳素抑制因子（PIF）的分泌，并在下午抑制PIF的分泌。
