Parallel competitive binding and metabolic endpoint assays for hCG based on rabbit granulosa cells

A competitive binding assay for hCG is described, in which live rabbit granulosa cells adhering to small tubes provide solid-phase binding sites. Parallel assays, in which the synthesis of progestagens and the incorporation of [3H]acetate into lipid serve as endpoints, are also described. The assays are sensitive, reproducible and precise and should be both economical and convenient for studies on the relationship between the molecular structure and the biological activity of hCG and LH.