Lorenzo A V, Winston K R, Welch K, Adler J R, Granholm L
Z Kinderchir. 1983 Dec;38 Suppl 2:68-70. doi: 10.1055/s-2008-1063079.
Tissue dehydration, including that of the brain, is a natural part of maturation. In the newborn it is accompanied by an acute salt water diuresis which is particularly pronounced in the premature infant. The decrease in cranial volume and fall in intracranial pressure to subatmospheric levels observed in premature infants after birth suggests that the brain shares in this process. Since fluid homeostasis is normally under hormonal control, the inordinate loss of fluid in the prematurely born may be attributable to a hormonal imbalance. The possibility that prolactin, a proven osmoregulatory hormone in submammalian species but not in mammals and primates, may have an important role in this process is suggested by recent evidence that prolactin regulates tissue water in fetal and newborn animals. If this hormone assists in the regulation of water and electrolyte content of the brain during the perinatal period then prolactin receptors might be expected at blood-brain and blood-CSF barriers. Our study with preterm, term and adult rabbits indicates that prolactin receptors are present and in much higher concentrations in the choroid plexus than in other tissues examined. Specific binding of prolactin to receptors on tissues normally is observed to increase with age. Since binding to the choroid plexus decreased with age it would suggest that the effect of prolactin on choroid plexus function may be more important during the perinatal than later stages of development.
包括脑在内的组织脱水是成熟过程中的自然现象。在新生儿中，这伴随着急性盐水利尿，在早产儿中尤为明显。出生后早产儿颅骨体积减小、颅内压降至低于大气压水平，这表明脑也参与了这一过程。由于液体平衡通常受激素控制，早产儿过度的液体流失可能归因于激素失衡。催乳素在非哺乳动物中是一种已被证实的渗透压调节激素，但在哺乳动物和灵长类动物中不是，最近有证据表明催乳素调节胎儿和新生动物的组织水分，这提示催乳素在这一过程中可能起重要作用。如果这种激素在围产期协助调节脑的水和电解质含量，那么在血脑屏障和血脑脊液屏障处可能会有催乳素受体。我们对早产、足月和成年兔子的研究表明，催乳素受体存在，且在脉络丛中的浓度比在其他检测组织中高得多。通常观察到催乳素与组织受体的特异性结合随年龄增加。由于与脉络丛的结合随年龄减少，这表明催乳素对脉络丛功能的影响在围产期可能比发育后期更重要。
