ÜBER DIE DURCH UNSPEZIFISCHE SUBSTANZEN BEDINGTE ÄNDERUNG DER QUANTITATIVEN UND QUALITATIVEN WIRKSAMKEIT VON GONADOTROPINEN BEI DER BIOLOGISCHEN AKTIVITÄTSBESTIMMUNG

Abstract

ABSTRACT The activity of chorionic gonadotrophin (HCG) injected in solutions containing different nonspecific substances (polyvinylpyrrolidone, gelatine, tragacanth = »depot-media« is compared with the activity of HCG in distilled water. Intact immature female rats are used for the bioassays, which differ only in injection schedule or the response measured (uterine resp. ovarian weight). Depending on the injection schedule used and the response measured the results of the various bioassays in intact immature rats are different, when one and the same depot-medium is used. Significant indices of discrimination as well as significant slope differences of dose-response curves are observed. The addition of a biologically inactive kaolin extract prepared according to the »crude kaolin-acetone method« to a gonadotrophic extract from the urine of postmenopausal women produced a significant decrease in activity in one type of assay, and a significant slope difference of dose-response curves in another one. In view of these results the difficulties arising for the demonstration of qualitative differences in gonadotrophic preparations and for expressing bioassay-results in terms of the International Reference Preparation are discussed.