大鳞大马哈鱼垂体生长激素的分离、纯化与鉴定

Isolation,Purification and Characterization of Growth Hormone from Chinook Salmon Pituitary ,

应用ConA-Sepharose 4B亲和层析、凝胶过滤及离子交换层析等技术从大鳞大马哈鱼(Oncorhynchus tshawytscha)垂体中分离纯化了具有生物活性的生长激素(sGH)。用放射受体测定法(RRA)检测sGH组分的生物活性,结果表明纯化的8GH制品具有与兔肝细胞GH受体结合的生物活性。用放射免疫测定法(RIA)和酶联免疫吸附测定法(ELISA)分别检测了另两种垂体激素-催乳激素(PRL)和促性腺激素(GTH)在纯化的sGH制品中的残留量均在0.5％以下。用SDS-聚丙烯酰胺凝胶电泳SDS-PAGE评价sGH制品的电泳纯度并测定了其分子量为22000左右。等电聚焦电泳表明该种鱼GH由等电点分别为6.3和6.6的两种形式的分子组成。

Growth hormone (GH) was isolated from chinook salmon (Oncorhynchus tshawytscha) pituitary by chromatography on Concanavalin A, gel filtratian on Ultr-ogel AcA54, and ion-exchange chromatography on CM-Biogel A.The GH biological activity of fractions obtained is measured by using mammalian GH radioreceptor assay (RRA).In this RRA system, rabbit liver membrane preparation as GH receptor was used, and bovine GH as standard.The RRA assay showed that sGH preparation had a high affinity for rabbit liver cells GH receptor.The contaminations of the other pituitary hormones (Gonadotropin and prolactin) in sGH preparation were less than 0.5% determined by ELISA or RIA.The purified sGH had a molecular weight of about 22kD dalton determined by SDS-PAGE.Isoelectric focussing showed that sGH consisted of two protein bands having isoelectric points (PI) of 6.6 and 6.3, respectively.These values has been compared to the corresponding data of GHs from other fishes.