ASSAY OF FOLLICLE-STIMULATING HORMONE IN THE HYPOPHYSECTOMIZED ESTROGEN-TREATED IMMATURE FEMALE RAT1

Abstract
An assay for pituitary follicle-stimulating hormone (FSH) using the estrogen-treated, hypophysectomized immature rat is presented. Linear dose-response curves, which correlated with histological evidence of maturation of follicles, were observed with various preparations tested for FSH activity. Crude pituitary tissue from several species, as well as purified pituitary gonadotropins, were assayed for FSH content; potencies were evaluated by comparison of the slopes of the regression lines produced.