beta-Lipotropin is the major opioid-like peptide of human pituitary and rat pars distalis: lack of significant beta-endorphin.
beta-Lipotropin is the major opioid-like peptide of human pituitary and rat pars distalis: lack of significant beta-endorphin.
复制标题
β-Lipotropin 是人垂体和大鼠远端的主要阿片样肽：缺乏显着的 β-内啡肽。
DOI：
10.1073/pnas.75.6.2950
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发表时间：
1978
影响因子：
11.1
通讯作者：
D. Krieger
中科院分区：
文献类型：
--
作者：
A. Liotta;T. Suda;D. Krieger
β-促脂素是人垂体和大鼠远侧部的主要阿片肽，其浓度基本上与促肾上腺皮质激素等摩尔。当新鲜获得的非冷冻大鼠前垂体匀浆与0.2 M盐酸，约98%的免疫反应性检测利用抗血清，交叉反应，同样与β-促脂素和β-内啡肽共洗脱125 I-标记的人β-促脂素分子筛层析。剩余的活性用合成的人类β-内啡肽洗脱。对人垂体也获得了类似的结果。解冻组织的HCl均质化或新鲜组织与乙酸的均质化产生显著更高浓度的β-内啡肽和降低浓度的β-促脂素。在人类受试者中，使用胰岛素诱导的低血糖或加压素给药进行急性垂体前叶刺激与血浆β-促脂素和促肾上腺皮质激素水平升高相关。在达到峰值浓度时，未检测到显著水平的β-内啡肽。这些数据表明人类脑垂体中缺乏大量的β-内啡肽。此外，似乎没有特定的垂体内β-促脂素转化为β-内啡肽。
beta-Lipotropin is the predominant opioid peptide of the human pituitary and rat pars distalis and is present in concentrations essentially equimolar with corticotropin. When freshly, obtained nonfrozen rat anterior pituitaries were homogenized with 0.2 M HCl, approximately 98% of the immunoreactivity detected utilizing an antiserum that crossreacts equally with beta-lipotropin and beta-endorphin coeluted with 125I-labeled human beta-lipotropin upon molecular sieve chromatography. The remainder of the activity eluted with synthetic human beta-endorphin. Similar results were obtained for human pituitary. HCl homogenization of thawed tissue or homogenization of fresh tissue with acetic acid yielded substantially greater concentrations of beta-endorphin and decreased concentrations of beta-lipotropin. In human subjects, acute anterior pituitary stimulation using either insulin-induced hypoglycemia or vasopressin administration was associated with increased plasma beta-lipotropin and corticotropin levels. At the time of peak concentrations, no significant levels of beta-endorphin were detectable. These data indicate the lack of significant amounts of beta-endorphin in human pituitary. Additionally, there appears to be no specific intrapituitary conversion of beta-lipotropin to beta-endorphin.