Thyroid Hormone Action at the Cell Level

Abstract

(Second of Two Parts)Inter-relation between Thyroid Hormone, Catecholamines and β-Adrenergic ReceptorsPrevious speculation and many data in this area are omitted for the sake of brevity. Some of the manifestations of clinical thyrotoxicosis resemble excessive adrenal medullary activity. Moreover, the β-adrenergic blocking agent, propranolol, has been successfully employed in the management of some manifestations of thyrotoxicosis.91 It is therefore appropriate to mention recent findings suggesting an increased number of β-adrenergic receptor sites in the cardiac plasma membranes of experimental hyperthyroid rats.92 93 94 Cardiac membranes (in a mixture including microsomes) from rats rendered toxic with excess thyroid hormone exhibited an increased . . .