Ulus I H, Scally M C, Wurtman R J
J Pharmacol Exp Ther. 1978 Mar;204(3):676-82.
Treatments that increase the release of acetylcholine from the splanchnic nerve have previously been shown to induce the enzyme tyrosine hydroxylase in adrenal chromaffin cells. Such treatments include the systemic administration of the drugs phenoxybenzamine and 6-hydroxydopamine, insulin-induced hypoglycemia, and prolonged exposure to cold. We have reported that the administration of choline also induces the adrenal enzyme and have suggested that the mechanism of this induction involves an increase in the amount of acetylcholine released each time the splanchnic nerve fires. In the present studies, rats received both choline and one of the above treatments. Choline caused an augmentation of the adrenomedullary response to each of the treatments, but it had no apparent effect on a presynaptic enzyme, choline acetyltransferase. These observations strongly support the view that choline availability determines both the amount of acetylcholine present in nerve terminals and the amount liberated when cholinergic neurons fire.
先前已表明，增加内脏神经乙酰胆碱释放的治疗方法可诱导肾上腺嗜铬细胞中的酪氨酸羟化酶。此类治疗方法包括系统给予苯氧苄胺和6-羟基多巴胺、胰岛素诱导的低血糖以及长时间暴露于寒冷环境。我们曾报道，给予胆碱也可诱导肾上腺中的这种酶，并提出这种诱导机制涉及每次内脏神经放电时释放的乙酰胆碱量增加。在本研究中，大鼠同时接受胆碱和上述治疗方法之一。胆碱增强了肾上腺髓质对每种治疗方法的反应，但对突触前酶胆碱乙酰转移酶没有明显影响。这些观察结果有力地支持了这样一种观点，即胆碱的可利用性决定了神经末梢中乙酰胆碱的含量以及胆碱能神经元放电时释放的乙酰胆碱量。
