[Identification and characteristics of the beta-adrenergic receptors in the membranes of cultured endothelial cells of the human pulmonary artery].

The properties of beta-adrenoreceptors (beta-AR) have been studied in endothelial cells from the human pulmonary artery (EPA) and umbilical vein (EUV). [125I] Iodosyanopindolol binding assay revealed the amount of 22 and 12 fmol/10(6) cells as well as Kd = 92 and 52 pM for EPA and EUV, respectively. Adrenergic agonists increased the cAMP levels in EPA in the order of potency characteristic for beta 2-AR: isoproterenol greater than epinephrine greater than norepinephrine. Basing on the results obtained in the present study and the literature data a conclusion is made that the properties of beta-AR in vascular endothelial cells do not practically depend on their localization, suggesting universality of their function within the vascular system.