Kawazoe I, Kawauchi H, Hirano T, Naito N
Gen Comp Endocrinol. 1987 Mar;65(3):423-31. doi: 10.1016/0016-6480(87)90128-6.
Melanin concentrating hormone (MCH) is a heptadecapeptide isolated from chum salmon (Oncorhynchus keta) pituitaries. The peptide has been isolated from whole brain extract at a low yield of 1.2 micrograms/1300 brains. MCH activity in the hypothalamus was characterised by in vitro scale bioassay and radioimmunoassay. Specificity of these assay systems was examined with neurotransmitters such as epinephrine, norepinephrine, and dopamine, hypothalamic hormones such as somatostatin, isotocin, Arg-vasotocin, oxytocin, and Arg-vasopressin, and salmon prolactin and its chymotryptic peptide or salmon PRL176-187. Among them only salmon PRL176-187 exhibited weak activities in both assays. The neurotransmitters were 10(4) to 10(5) times less potent than MCH in the bioassay. MCH concentrations in a pituitary and a hypothalamus were estimated as 5300 +/- 750 ng (ca. 106 micrograms/g) and 48 +/- 9.5 ng (ca. 1.6 micrograms/g), respectively, by radioimmunoassay. Lysyl endopeptidase digestion of the hypothalamic extract resulted in a significant increase of biological activity as well as of immunoreactivity. Gel filtration of the hypothalamic extract and subsequent enzymatic digestion revealed that the fractions at higher molecular weight were contributory to the increase in the activities.
黑色素聚集激素（MCH）是一种从大麻哈鱼（Oncorhynchus keta）垂体中分离出的十七肽。该肽已从全脑提取物中分离出来，产率较低，为1.2微克/1300个脑。下丘脑的MCH活性通过体外生物测定法和放射免疫测定法进行表征。使用肾上腺素、去甲肾上腺素和多巴胺等神经递质、生长抑素、异催产素、精氨酸血管催产素、催产素和精氨酸加压素等下丘脑激素以及鲑鱼催乳素及其胰凝乳蛋白酶肽或鲑鱼PRL176 - 187对这些测定系统的特异性进行了检测。其中只有鲑鱼PRL176 - 187在两种测定中表现出微弱活性。在生物测定中，神经递质的效力比MCH低10^4至10^5倍。通过放射免疫测定法估计，垂体和下丘脑中MCH的浓度分别为5300±750纳克（约106微克/克）和48±9.5纳克（约1.6微克/克）。下丘脑提取物经赖氨酰内肽酶消化后，生物活性和免疫反应性均显著增加。下丘脑提取物的凝胶过滤及随后的酶消化表明，较高分子量的级分对活性增加有贡献。
