The β3-adrenoceptor is a G protein-coupled receptor which mediates metabolic functions of the endogenous catecholamines epinephrine and norepinephrine. Questions exist regarding distribution of the β3-adrenoceptor in human tissue. In order to examine the distribution of β3-adrenoceptor mRNA in human tissues, we used sensitive and specific RNase protection assays without previous PCR amplification in an extensive list of human tissues. We confirm the presence of β3-adrenoceptor mRNA in human white fat from several locations, gall bladder, and small intestine, as well as extend the distribution of β3-adrenoceptor mRNA to previously uncharacterized human tissues such as stomach and prostate. The presence of β3-adrenoceptor mRNA in human white adipose tissue has important implications regarding possible use of β3-adrenoceptor selective agonists as anti-obesity agents, and the demonstration of β3-adrenoceptor mRNA in a number of gastrointestinal tissues and prostate raises the question of the role of the β3-adrenoceptor in motility and secretory processes. © 1995.