Zakarian S, Smyth D G
Biochem J. 1982 Mar 15;202(3):561-71. doi: 10.1042/bj2020561.
beta-Endorphin, the most potent known naturally occurring analgesic agent, is found in pituitary and brain in company with a series of structurally and biosynthetically related peptides that are essentially devoid of opiate activity. In studies of beta-endorphin it is important to discriminate between the active and inactive forms of the peptide. This review describes the use of chemical and immunological methods for localizing the peptides in the tissues, extracting and resolving the peptides by chromatography, and determining the concentrations of the peptides by radioimmunoassay. These approaches have allowed the distribution of beta-endorphin and its related peptides to be assigned unequivocally in regions of rat pituitary and brain. It has been found that the multifunctional corticotropin-endorphin prohormone can undergo processing by different mechanisms in different tissues, permitting the intrinsic activities of its fragments to be expressed selectively. The different processing patterns can be attributed to the existence of highly specific enzymes, characteristic of individual cells, which regulate the formation of this potent opiate.
β-内啡肽是已知最有效的天然存在的镇痛剂，它与一系列在结构和生物合成上相关的肽一起存在于垂体和大脑中，这些肽基本上没有阿片样活性。在β-内啡肽的研究中，区分该肽的活性形式和非活性形式很重要。这篇综述描述了使用化学和免疫学方法在组织中定位肽、通过色谱法提取和分离肽以及通过放射免疫测定法测定肽的浓度。这些方法使得能够明确确定β-内啡肽及其相关肽在大鼠垂体和大脑区域中的分布。已发现多功能促肾上腺皮质激素-内啡肽前体激素可以在不同组织中通过不同机制进行加工，从而使其片段的内在活性得以选择性表达。不同的加工模式可归因于存在高度特异性的酶，这些酶是单个细胞所特有的，它们调节这种强效阿片样物质的形成。
