Biological determination of inhibin in rat ovarian-cell culture medium.

ABSTRACT

Rat ovarian-cell culture medium contains steroids and inhibin material that are able to influence basal and LHRH-stimulated secretion of FSH and LH from dispersed pituitary cells. Studies on procedures to remove steroids, such as ethyl acetate extraction and charcoal dextran adsorption, showed that adsorption of the culture medium with 0.5 to 1.0% charcoal and 0.05 to 0.1% dextran, respectively, was the optimal method to eliminate most of the steroids in the medium without a detrimental effect on inhibin activity. The inclusion of serum or bovine albumin in the culture medium after the culture protected the inhibin from adsorption by the charcoal dextran treatment. The inhibin present in the rat ovarian-cell culture medium treated with 1.0% charcoal 0.1% dextran behaved like the inhibin reference standard (from rete testis fluid of the sheep RTFS) in the basal secretion of FSH and the LHRH-stimulated secretion of FSH and LH in the in-vitro bioassay.