Dyball R E
J Endocrinol. 1975 Dec;67(3):453-8. doi: 10.1677/joe.0.0670453.
Isolated rat neural lobes were incubated in vitro in Locke's solution containing anaesthetic quantities of urethane, pentobarbitone or tribromoethanol. The oxytocin content of the incubation medium was estimated before, during and after stimulation of the tissue by raising the potassium chloride concentration from 5-6 to 56 mmol/l. Urethane (25 mmol/l) significantly potentiated oxytocin release (P less than 0-01) whereas tribromoethanol (0-5 mmol/l) had no obvious effect and pentobarbitone (0-4 mmol/l) significantly (P less than 0-01) inhibited its release. Reduction of the sodium chloride concentration in the medium potentiated the release of oxytocin in each case but did not alter its pattern. Urethane which increased secretion of oxytocin also increased calcium ion uptake by the neural lobes and pentobarbitone which decreased oxytocin release decreased calcium ion uptake. The results may explain why the blood concentration of the neurohypophysial hormones tends to be higher in rats anaesthetized with urethane than with tribromoethanol. Inhibition of hormone release by pentobarbitone suggests that this anaesthetic is unsuitable for use in studies of neurohypophysial hormone release. A partial explanation of the anaesthetic properties of urethane and pentobarbitone may also have been found if the release of neurotransmitter substances is influenced in a similar manner.
将分离出的大鼠神经叶在含有麻醉剂量氨基甲酸乙酯、戊巴比妥或三溴乙醇的洛克溶液中进行体外培养。在将氯化钾浓度从5 - 6毫摩尔/升提高到56毫摩尔/升以刺激组织之前、期间和之后，对培养液中的催产素含量进行了评估。氨基甲酸乙酯（25毫摩尔/升）显著增强了催产素的释放（P小于0.01），而三溴乙醇（0.5毫摩尔/升）没有明显作用，戊巴比妥（0.4毫摩尔/升）则显著（P小于0.01）抑制其释放。降低培养液中的氯化钠浓度在每种情况下都增强了催产素的释放，但没有改变其模式。增加催产素分泌的氨基甲酸乙酯也增加了神经叶对钙离子的摄取，而减少催产素释放的戊巴比妥则减少了钙离子的摄取。这些结果可能解释了为什么在用氨基甲酸乙酯麻醉的大鼠中，神经垂体激素的血药浓度往往高于用三溴乙醇麻醉的大鼠。戊巴比妥对激素释放的抑制表明这种麻醉剂不适用于神经垂体激素释放的研究。如果神经递质物质的释放也受到类似方式的影响，那么也可能找到了对氨基甲酸乙酯和戊巴比妥麻醉特性的部分解释。
