Abstract
Adipocytes from thyroidectomized rats contain 3 times less [3H]dihydroalprenolol-binding sites (.beta.-adrenergic receptors) than adipocytes from euthyroid animals. This alteration is not solely due to cell-size differences, but also to a thyroidectomy-induced defect in .beta.-adrenergic receptor density per adipocyte surface area, a defect that is corrected by triiodothyronine treatment.