HORMONE RECEPTORS

THE endocrine and nervous systems communicate information between cells. Whereas in the nervous system the various messages travel along distinct channels, the glands of the endocrine system release their messages into the bloodstream, which delivers them indiscriminately to target and nontarget tissues. Cells that are targets for a particular hormone contain specialized molecules called receptors that bind the hormone and subsequently mediate its cellular actions. The roles of a receptor are two: the first is to distinguish a particular signal from the jumble of hormones and other molecules impinging on the cell, and the second is to relay this signal. © 1979, Massachusetts Medical Society. All rights reserved.