Partial purification and characterization of a renotropic fraction from ovine pituitaries.
Partial purification and characterization of a renotropic fraction from ovine pituitaries.
复制标题
绵羊垂体促肾素部分的部分纯化和表征。
DOI：
10.1073/pnas.79.21.6675
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发表时间：
1982
影响因子：
11.1
通讯作者：
Liddle,GW
中科院分区：
文献类型：
--
作者：
Nomura,K;Puett,D;Nicholson,WE;Liddle,GW
先前已经确定垂体切除术会导致大鼠肾萎缩，而粗垂体衍生成分可以有效地将肾脏重量恢复到相同体重的完整动物的预期水平。本文报道了从绵羊垂体中提取的促肾性粗提取物的大量纯化，纯化后的提取物能够使垂体切除的去势大鼠的肾脏重量恢复到正常水平。例如，每天皮下注射5次（135微克/天）后，干肾重量、总肾蛋白和DNA显著增加。垂体衍生的部分不含促生长激素，仅含有微量促肾上腺皮质激素、γ -脂促素、加压素和催乳素，促甲状腺激素和促卵泡素含量较低。每日注射催乳素、促甲状腺素和卵泡素各20微克，均不能刺激去垂体大鼠的肾脏生长。因此，这些因素似乎不太可能是垂体部分治疗后观察到的肾脏增生的原因。纯化后的嗜肾性组分的等电pH值在8 ~ 9之间。在聚丙烯酰胺凝胶电泳中，在洗涤剂和还原剂存在的情况下，亲肾性部分显示出两条主要带和一条次要带，其迁移率与标准lutropin制剂相对应。嗜肾性部分与一种针对lutropin α亚基的抗血清表现出相当大的交叉反应性，表明存在常见的糖蛋白激素亚基。此外，纯化后的部分在体外刺激Leydig肿瘤细胞产生类固醇。然而，值得注意的是，135微克/天的标准羊鲁特素在去垂体的阉割大鼠中没有表现出嗜肾活性，尽管在两倍剂量的剂量下发现了效果。看来嗜肾活性代表了一种垂体物质，很难从lutropin中分离出来。
It has been previously established that hypophysectomy leads to renal atrophy in rats and that a crude pituitary-derived fraction is effective in restoring kidney weight to the level expected for intact animals of the same body weight. This paper reports that considerable purification of the crude renotropic fraction from ovine pituitaries has been achieved and that the purified fraction is capable of restoring kidney weights of hypophysectomized castrated rats to normal values. For example, after five daily subcutaneous injections (135 micrograms/day) there were significant increases in dry kidney weight and total renal protein and DNA. The pituitary-derived fraction was devoid of somatotropin, contained only trace amounts of corticotropin, gamma-lipotropin, vasopressin, and prolactin, and had only low levels of thyrotropin and follitropin. Daily injections of prolactin, thyrotropin, and follitropin in doses of 20 micrograms each failed to stimulate renal growth in hypophysectomized rats. Thus, it seems highly unlikely that these factors are responsible for the observed renal hyperplasia after treatment with the pituitary fraction. The purified renotropic fraction had an isoelectric pH between 8 and 9. On polyacrylamide gel electrophoresis in the presence of detergent and a reducing agent, the renotropic fraction exhibited two major bands and one minor band with mobilities that corresponded to those of a standard lutropin preparation. The renotropic fraction exhibited considerable crossreactivity with an antiserum directed against the lutropin alpha subunit, suggesting the presence of the common glycoprotein hormone subunit. Moreover, the purified fraction stimulated steroid production by Leydig tumor cells in vitro. It is noteworthy, however, that standard ovine lutropin at 135 micrograms/day failed to exhibit renotropic activity in hypophysectomized castrated rats, although effects were noted at twice that dose. It appears that the renotropic activity represents a pituitary substance that can be separated from lutropin only with difficulty.