A CLINICAL ROUTINE-METHOD FOR THE QUANTITATIVE DETERMINATION OF GONADOTROPHINS IN 24-HOUR URINE SAMPLES

Abstract

A rapid new method using simple and inexpensive apparatus is described for extracting gonadotrophins from 24-hour urine specimens. The method is based on the extraction of the gonadotrophic activity from a tannic acid precipitate by means of ammonium acetate-ammonium hydroxide-alcohol mixtures, and the counter current principle is used very simply by allowing a thick filter cake of hyflosupercel retaining the gonadotrophin precipitate to act as a column. Extracts obtained using this procedure contain less inert material than those obtained by other methods. The extracts are not contaminated with protein-bound tannic acid, estrogen or other augmenting substances and are very soluble. The toxicity of the extracts for immature mice is low, and the method allows one rapid procedure to be used in both hypergonadotrophic and hypogonadotrophic clinical conditions. Recovery experiments and repeated assays on pools of urine reveal a high degree of consistency of results. In an analysis of the day-to-day gonadotrophin excretion of 2 subjects, little daily variation was found indicating that variation in gonadotrophin excretion previously reported by various authors may be due to errors in the extraction methods employed.