Expression of transcripts for beta 1-, beta 2-, and beta 3-adrenergic receptors (beta 1-AR, beta 2-AR, and beta 3-AR, respectively) was investigated in porcine tissues. Northern blot analysis of total RNA indicated hybridization of the rat beta 1-AR probe to transcripts of approximately 3.0-kb in heart and lung and 2.9-kb in perirenal, omental, and subcutaneous adipose tissue. Hybridization of the hamster beta 2-AR probe with total RNA revealed transcripts of approximately 1.8-kb in the heart, 2.0-kb in the lung, and 2.0-kb in perirenal, omental, and subcutaneous adipose tissue; a minor transcript of 1.8-kb was also observed in the perirenal tissue. Northern blot analysis of poly (A+) RNA from porcine adipose tissue with the mouse beta 3-AR probe revealed no detectable signals in heart and lung but detected a major 2.2-kb transcript and a minor 1.9-kb transcript in subcutaneous adipose tissue. The expression of porcine beta 1-AR and beta 2-AR transcripts was compared in perirenal, omental, and subcutaneous adipose depots. The expression of beta 1-AR transcripts was four to five times greater in the perirenal depot than in the omental depot and two to three times greater in the subcutaneous depot than in the omental depot. The expression of beta 2-AR mRNA seemed to be the same in all three depots.