Wang Y N, Lindberg I
Cell Tissue Res. 1986;244(1):77-85. doi: 10.1007/BF00218384.
The distribution and characterization of the opioid octapeptide met5-enkephalin-arg6-gly7-leu8 (met5-enk-arg6-gly7-leu8) within the gastrointestinal tract of the rat has been determined by immunohistochemistry and radioimmunoassay by use of a newly developed antibody to met5-enk-arg6-gly7-leu8. With both techniques, met5-enk-arg6-gly7-leu8-immunoreactivity (met5-enk-arg6-gly7-leu8-IR) was detected in all regions of the gastrointestinal (GI) tract except the esophagus. The highest concentration of immunoreactive met5-enk-arg6-gly7-leu8 was observed in the colon, while intermediate concentrations were found in the stomach, duodenum, jejunum, and ileum. Immunostained somata were observed chiefly in the myenteric plexus; immunostained processes were present primarily in the myenteric plexus and the circular muscle layer. This distribution pattern is similar to that previously observed with antiserum to met5-enkephalin-arg6-phe7 (met5-enk-arg6-phe7). Chromatographic analysis of met5-enk-arg6-gly7-leu8-immunoreactive peptides extracted from the GI tract revealed the presence of an immunoreactive peptide of high molecular weight which accounted for approximately three-quarters of met5-enk-arg6-gly7-leu8-IR in both stomach and colon. These findings suggest a role for peptides related to the octapeptide met5-enk-arg6-gly7-leu8 in the regulation of GI function.
通过免疫组织化学和放射免疫测定法，利用新开发的针对甲硫氨酸脑啡肽-精氨酸-甘氨酸-亮氨酸（met5-enk-arg6-gly7-leu8）的抗体，确定了大鼠胃肠道中甲硫氨酸脑啡肽八肽（met5-enk-arg6-gly7-leu8）的分布和特征。使用这两种技术，在胃肠道（GI）除食管外的所有区域均检测到了met5-enk-arg6-gly7-leu8免疫反应性（met5-enk-arg6-gly7-leu8-IR）。在结肠中观察到免疫反应性met5-enk-arg6-gly7-leu8的浓度最高，而在胃、十二指肠、空肠和回肠中发现了中等浓度。免疫染色的神经元胞体主要见于肌间神经丛；免疫染色的神经纤维主要存在于肌间神经丛和环行肌层。这种分布模式与先前用针对甲硫氨酸脑啡肽-精氨酸-苯丙氨酸（met5-enk-arg6-phe7）的抗血清观察到的模式相似。对从胃肠道中提取的met5-enk-arg6-gly7-leu8免疫反应性肽进行色谱分析，发现存在一种高分子量的免疫反应性肽，其在胃和结肠中约占met5-enk-arg6-gly7-leu8-IR的四分之三。这些发现表明，与八肽met5-enk-arg6-gly7-leu8相关的肽在胃肠道功能调节中发挥作用。
