神经垂体激素的体外释放

The rate of release of neurohypophysial hormones in vitro, using isolated, halved neural lobes of the rat in an incubation medium containing excess K(+) and Ca(2+), was measured. The highest average rate of release was observed between 10 and 20 min after commencement of incubation.2. Incubation of isolated, halved rat neural lobes in the presence of acetylcholine, with or without eserine, did not stimulate hormone release. When complete isolated hypothalamo-neurohypophysial systems were incubated in a suspension medium containing 10(-7) mg/ml. acetylcholine a significant increase in the release of oxytocin occurred (P < 0.01); the increase in vasopressin release was less pronounced (P < 0.05).3. Uptake of O(2) by the isolated, halved neural lobes and the hypothalamo-neurohypophysial systems continued for 2-3 hr, i.e. in excess of the experimental incubation time.4. During the first 40 min of incubation the control halved neural lobes increased in weight; the neural lobes incubated in buffer containing high potassium and calcium showed no increase in weight.5. Neural lobes incubated in buffer containing excess K(+) and Ca(2+) contained about 3 times as much potassium as controls. The sodium content was not affected significantly.6. Factors involved in the process of neurohypophysial hormone release are discussed.

采用含有过量钾离子（K⁺）和钙离子（Ca²⁺）的孵育培养基，对大鼠分离的半侧神经垂体叶进行体外培养，测定神经垂体激素的释放速率。在孵育开始后的10至20分钟之间观察到最高平均释放速率。
在有或没有毒扁豆碱存在的情况下，将分离的半侧大鼠神经垂体叶与乙酰胆碱一起孵育，并未刺激激素释放。当完整的下丘脑 - 神经垂体系统在含有10⁻⁷mg/ml乙酰胆碱的悬浮培养基中孵育时，催产素的释放显著增加（P < 0.01）；抗利尿激素释放的增加则不太明显（P < 0.05）。
分离的半侧神经垂体叶和下丘脑 - 神经垂体系统对氧气（O₂）的摄取持续2至3小时，即超过实验孵育时间。
在孵育的前40分钟内，对照半侧神经垂体叶重量增加；在含有高钾和钙的缓冲液中孵育的神经垂体叶重量没有增加。
在含有过量钾离子（K⁺）和钙离子（Ca²⁺）的缓冲液中孵育的神经垂体叶所含钾离子约为对照的3倍。钠含量未受到显著影响。
讨论了神经垂体激素释放过程中涉及的因素。

Release of neurohypophysial hormones in vitro.