Receptors and Hormone Action, Volume III, is part of a multivolume series that summarizes advances in the field of hormone action. The articles contained in these books are oriented toward a description of basic methodologies and model systems used in the exploration of the molecular bases of hormone action, and are aimed at a broad spectrum of readers including those who have not yet worked in the field as well as those who have considerable expertise in one or another aspect of hormone action. This book opens with a chapter on the physiological properties of the thyroid hormone receptors in the intact animal. This is followed by separate chapters on ß-adrenergic receptors; the study of hormone-receptor interaction by measuring the biological responses induced by the actions of gonadotropins on Leydig cells; chemical and immunochemical properties of hCG and PMSG treated with glycosidases; and binding of follitropin (FSH) to rat testes. Subsequent chapters deal with the control of changes of gonadotropin responsiveness of the granulosa cell during follicular maturation; regulation of prolactin receptors by steroid hormones; and the role of membrane protein phosphorylation in the effects of neurotransmitters.