Autoradiographic mapping of beta-adrenoceptors in human skin

A high density of β₂-adrenoceptors has been found in human skin. Using autoradiographic mapping we investigated the distribution of β₁- and β₂-receptors in normal and diseased human skin. Cryostat sections of human skin obtained at biopsy were incubated with [¹²⁵I]-iodocyanopindolol and nonspecific binding was identified by incubation of adjacent sections with 200 μM (-)-isoproterenol; β₂-receptors were visualized using CGP 20712A and β₁-receptors using ICI 118,551 as competing agents. The epidermis was densely labelled with an even distribution throughout all layers. Most of the β-receptors were of the β₂-subtype, with practically no β₁-receptors. β-Receptors were also localized to eccrine sweat glands, dermal blood vessels, and perivascular inflammatory cells, but there was no labelling of sebaceous glands. Topical glucocorticoids caused an increase in the density of epidermal β-receptors. We conclude that keratinocytes and eccrine sweat glands express high densities of β₂-receptors, suggesting that they may have a physiological role in the regulation of these cells.