Sladek C D, Knigge K M
Endocrinology. 1977 Dec;101(6):1834-8. doi: 10.1210/endo-101-6-1834.
The rat hypothalamo-neurohypophyseal system (HNS) in organ culture has been used as an in vitro system for studying the osmotic control of vasopressin (VP) release. The HNS retains osmotically sensitive components as demonstrated by changes in the rate of VP release following alterations in the osmolality of the culture medium. Increasing the osmolality from 295 to 305 mosmol/kg H2O by the addition of NaCl resulted in a 2.5-fold increase in VP release. VP release was significantly decreased subsequent to reducing the osmolality from 295 to 280 mosmol/kg H2O by the addition of distilled water. Also, VP release was stimulated when the osmolality was increased to 300 mosmol/kg H2O by the addition of mannitol, but not by additions of urea or glucose which resulted in comparable increases in the tonicity of the culture medium. These studies demonstrate that the HNS in organ culture responds appropriately to osmotic challenges within the physiological range, and support Verney's concept of an osmoreceptor inasmuch as both NaCl and mannitol were effective osmotic agents.
器官培养中的大鼠下丘脑 - 神经垂体系统（HNS）已被用作研究抗利尿激素（VP）释放的渗透压控制的体外系统。HNS保留了对渗透压敏感的成分，这通过培养基渗透压改变后VP释放速率的变化得以证明。通过添加NaCl将渗透压从295 mosmol/kg H₂O提高到305 mosmol/kg H₂O，导致VP释放增加了2.5倍。通过添加蒸馏水将渗透压从295 mosmol/kg H₂O降低到280 mosmol/kg H₂O后，VP释放显著减少。此外，通过添加甘露醇将渗透压提高到300 mosmol/kg H₂O时，VP释放受到刺激，但添加尿素或葡萄糖导致培养基张力类似增加时却没有这种情况，而尿素和葡萄糖会使培养基张力产生类似的增加。这些研究表明，器官培养中的HNS在生理范围内对渗透压挑战有适当反应，并支持弗尼关于渗透压感受器的概念，因为NaCl和甘露醇都是有效的渗透剂。
