Ferri G L, Morreale R A, Dockray G J
Peptides. 1986 Sep-Oct;7(5):735-9. doi: 10.1016/0196-9781(86)90087-2.
The presence of the proenkephalin A-derived peptide Met5-enkephalin-Arg6-Gly7-Leu8 was demonstrated throughout the human gastrointestinal tract. Highest concentrations of Met5-enkephalin-Arg6-Gly7-Leu8, as assessed by radioimmunoassay, were measured in the separated muscularis externa, while lower levels were found in the submucosa and only small amounts in the mucosa. The results are consistent with a neuronal location of this peptide in the human gut. Over 65% of total immunoreactivity coeluted with the authentic peptide in both molecular exclusion chromatography and HPLC, while most of the remainder activity eluted earlier on gel filtration. The latter material probably represents N-terminally extended Met5-enkephalin-Arg6-Gly7-Leu8. Taken together with previous studies, our results appear to indicate that there are important species differences in post-translational processing of proenkephalin A in gut nerves.
在整个人体胃肠道中均证实存在源自前脑啡肽A的肽甲硫氨酸脑啡肽-精氨酸-甘氨酸-亮氨酸。通过放射免疫测定法评估，在分离出的肌层中测得甲硫氨酸脑啡肽-精氨酸-甘氨酸-亮氨酸的浓度最高，而在黏膜下层中含量较低，在黏膜中仅有少量。这些结果与该肽在人体肠道中的神经元定位一致。在分子排阻色谱法和高效液相色谱法中，超过65%的总免疫反应性与 authentic 肽共洗脱，而其余大部分活性在凝胶过滤时较早洗脱。后一种物质可能代表N端延伸的甲硫氨酸脑啡肽-精氨酸-甘氨酸-亮氨酸。结合先前的研究，我们的结果似乎表明，肠道神经中前脑啡肽A的翻译后加工存在重要的物种差异。
