50% INHIBITION CONCENTRATION DETERMINING METHOD FOR CHEMICAL SUBSTANCE

摘要

PROBLEM TO BE SOLVED: To provide a method for evaluating the hormonic activity (50% inhibition concentration) of a chemical substance easily at a low cost with a small number of steps of operation. SOLUTION: A sample chemical substance is added to a solution containing a bound body of a hormone receptor and a ligand bound to the hormone receptor to emit fluorescence. The fluorescence intensity that changes according to the added concentration of the sample chemical substance is measured, and the concentration of the sample chemical substance showing one half of the difference between the fluorescence intensity of the solution containing the bound body of the hormone receptor and ligand, and the fluorescence intensity of the solution in a ligand separated state in the solution containing the hormone receptor and ligand is made 50% inhibition concentration. The ligand is preferably cumestrol or fluorescein cress-linked ethynil estradiol. As the hormone receptor, an estrogen receptor is given as an example.