7α-甲基-19-去甲睾酮的放射免疫测定及其在动物体内的药代动力学研究。

Radioimmunoassay of 7 alpha-methyl-19-nortestosterone and investigation of its pharmacokinetics in animals.

作者信息

Kumar N, Didolkar A K, Ladd A, Thau R, Monder C, Bardin C W, Sundaram K

机构信息

Center for Biomedical Research, Population Council, New York, NY 10021.

出版信息

J Steroid Biochem Mol Biol. 1990 Nov 30;37(4):587-91. doi: 10.1016/0960-0760(90)90405-a.

DOI:10.1016/0960-0760(90)90405-a

PMID:2278844

Abstract

A method for the measurement of 7 alpha-methyl-19-nortestosterone (7MENT) in serum/plasma by radioimmunoassay (RIA) is described. The antiserum, raised against 7 alpha-methyl-19-nortestosterone-3-O-oxime-bovine serum albumin, had a low titer (final dilution = 1:4500) and low affinity (Ka = 1.17 x 10(9) l/mol) but showed little or no cross-reactivity with several of the steroids tested. The sensitivity of the RIA was 28.2 pg/ml and the mean recovery of added cold steroid was 86 to 100%. Intra- and inter-assay coefficients of variation ranged from 4.3 to 7.3% and 7.3 to 8.4%, respectively. This RIA was used to follow plasma 7MENT levels after a single i.v. injection of the steroid in rats and rabbits. The metabolic clearance rates (MCR) of 7MENT as determined from the plasma disappearance curve for rats and rabbits were 50 l/day and 336 l/day, respectively. The MCR of 7MENT in rats and rabbits lies in the same range as for testosterone. When compared to other nortestosterone derivatives such as norethisterone, 7MENT is metabolized relatively faster.

摘要

本文描述了一种通过放射免疫分析法（RIA）测定血清/血浆中7α-甲基-19-去甲睾酮（7MENT）的方法。针对7α-甲基-19-去甲睾酮-3-O-肟-牛血清白蛋白制备的抗血清效价较低（最终稀释度=1:4500）且亲和力较低（Ka = 1.17×10⁹ l/mol），但与所检测的几种甾体几乎没有交叉反应。该放射免疫分析法的灵敏度为28.2 pg/ml，添加的冷甾体的平均回收率为86%至100%。批内和批间变异系数分别为4.3%至7.3%和7.3%至8.4%。该放射免疫分析法用于跟踪大鼠和兔子单次静脉注射该甾体后血浆中7MENT的水平。根据大鼠和兔子的血浆消失曲线确定的7MENT的代谢清除率（MCR）分别为50升/天和336升/天。大鼠和兔子中7MENT的MCR与睾酮处于相同范围。与其他去甲睾酮衍生物如炔诺酮相比，7MENT的代谢相对较快。