Key words: β₃-adrenergic receptor, structure, function, pharmacology, human heart.

Summary. β-adrenergic receptors have been subdivided into three types: β₁-, β₂- and β₃-adrenergic receptors. β₁-adrenergic receptors are predominant in the heart, β₂-adrenergic receptors – in the respiratory system, and β₃-adrenergic receptors – in the adipose tissues. However, since 1989, when β₃-adrenergic receptor was cloned, numerous biochemical and functional studies have confirmed its presence in various species and tissues, including the heart. Unlike β₁- and β₂-adrenergic receptors, it has been shown that β₃-adrenergic receptors possess the cardiodepressant effects in human ventricles, what did not fit to its stimulatory properties of adenylyl cyclase in other tissues. In this regard, the role of β₃-adrenergic receptors in the regulation of cardiac function may be of great importance in pathological conditions and remains undetermined, so far. In this review brief characterization of β₃-adrenergic receptors, concerning their structure, function and possible pathophysiological role is provided.

Correspondence to V. A. Skeberdis, Institute of Cardiology, Sukilėlių 17, 50157 Kaunas, Lithuania E-mail: arske@kmu.lt; vskeberd@aecom.yu.edu

Received 5 February 2004, accepted 30 March 2004