Hanbauer I, Kelly G D, Saiani L, Yang H Y
Peptides. 1982 May-Jun;3(3):469-73. doi: 10.1016/0196-9781(82)90109-7.
In adrenal chromaffin cells, various molecular forms of polypeptides cross-reacting with [met5]-enkephalin antisera are stored in granules together with catecholamines and soluble proteins. Splanchnic nerve stimulation increases the release of enkephalin-like peptides from the adrenal gland into the adrenal vein. The release of these peptides appears to be mediated by a cholinergic nicotinic receptor. Fractionation of plasma extracts on Bio-gel P-2 shows the presence of only low molecular weight peptides in the resting condition. The low molecular weight fraction contains mainly [met5]-enkephalin and [leu5]-enkephalin. When the splanchnic nerve is stimulated high and low molecular weight peptides are released and the amount of low molecular weight peptides in plasma is increased. The content of enkephalin-like peptides in adrenal venous plasma was similar in control and reserpinized dogs. Splanchnic nerve stimulation increased the peptide content but not the epinephrine content of plasma in reserpinized dogs. This also caused a fall of arterial blood pressure which could be prevented by pretreatment with naloxone. A decrease in blood pressure was also directly elicited by the injection of [met5]-enkephalin-[arg6-phe7]. The duration of the hypotensive effect of this peptide was prolonged by prior injection of captopril.
在肾上腺嗜铬细胞中，与[甲硫氨酸5]-脑啡肽抗血清发生交叉反应的多种分子形式的多肽，与儿茶酚胺和可溶性蛋白质一起储存在颗粒中。内脏神经刺激可增加肾上腺中脑啡肽样肽释放到肾上腺静脉中。这些肽的释放似乎由胆碱能烟碱受体介导。在Bio-gel P-2上对血浆提取物进行分级分离显示，在静息状态下仅存在低分子量肽。低分子量部分主要包含[甲硫氨酸5]-脑啡肽和[亮氨酸5]-脑啡肽。当刺激内脏神经时，高分子量和低分子量肽均被释放，血浆中低分子量肽的量增加。对照犬和利血平化犬的肾上腺静脉血浆中脑啡肽样肽的含量相似。内脏神经刺激增加了利血平化犬血浆中的肽含量，但未增加肾上腺素含量。这也导致动脉血压下降，预先用纳洛酮处理可预防这种情况。注射[甲硫氨酸5]-脑啡肽-[精氨酸6-苯丙氨酸7]也可直接引起血压下降。预先注射卡托普利可延长该肽降压作用的持续时间。
