Shin S H
Neuroendocrinology. 1980 Dec;31(6):375-9. doi: 10.1159/000123106.
Experiments were undertaken to demonstrate the existence of a physiological role of prolactin releasing factor (PRF). Hypothalamic control of prolactin secretion is achieved by secretion of prolactin inhibiting factor (PIF) and/or PRF. Since the putative PIF is dopamine, complete blockage of the dopaminergic PIF receptors should permit demonstration of PRF activity. The changes in prolactin concentration were monitored by taking a blood sample every 2 min through an indwelling atrial cannula. An excessive amount of pimozide (3 mg/kg) was used to block dopaminergic receptors and prolactin concentration was elevated as a result. This higher concentration of circulating prolactin was maintained for more than 30 h after a bolus injection of pimozide. In this situation, lacking functional dopaminergic PIF receptors, there were fluctuations in the circulating prolactin concentration throughout the experiment. If, after pimozide administration, rats were exposed to an acute (ether) stress, the stress consistently elevated the circulating prolactin concentration. Since there are no functional dopaminergic PIF receptors available under these conditions, a dopaminergic PIF cannot be involved in producing the prolactin surge induced by the acute stress. Therefore, these results suggest that a physiological PRF is involved in the generation of this prolactin surge, through the evidence is not direct.
开展了多项实验以证明催乳素释放因子（PRF）的生理作用的存在。催乳素分泌的下丘脑控制是通过催乳素抑制因子（PIF）和/或PRF的分泌来实现的。由于假定的PIF是多巴胺，多巴胺能PIF受体的完全阻断应能证明PRF的活性。通过经留置心房插管每2分钟采集一次血样来监测催乳素浓度的变化。使用过量的匹莫齐特（3毫克/千克）来阻断多巴胺能受体，结果催乳素浓度升高。在一次推注匹莫齐特后，这种较高的循环催乳素浓度维持了30多个小时。在这种情况下，由于缺乏功能性多巴胺能PIF受体，整个实验过程中循环催乳素浓度存在波动。如果在给予匹莫齐特后，大鼠受到急性（乙醚）应激，应激会持续升高循环催乳素浓度。由于在这些条件下没有可用的功能性多巴胺能PIF受体，多巴胺能PIF不可能参与产生急性应激诱导的催乳素激增。因此，这些结果表明，一种生理性PRF参与了这种催乳素激增的产生，尽管证据并不直接。
