Subtype-selective up-regulation of human saphenous vein \2-adrenoceptors by chronic \-adrenoceptor antagonist treatment

Abstract

To study beta-adrenoceptor antagonist-induced changes in human vascular beta-adrenoceptors, we determined the effects of chronic treatment with different beta-adrenoceptor antagonists without intrinsic sympathomimetic activity (ISA) on beta 2-adrenoceptor density (assessed by (-)-[125I]-iodopindolol binding) in human saphenous vein membranes obtained from patients undergoing coronary artery bypass grafting. In patients chronically treated with the non-selective beta-adrenoceptor antagonists propranolol or sotalol, the density of saphenous vein beta 2-adrenoceptors was significantly higher than in control (i.e. patients not treated with beta-adrenoceptor antagonists), whereas in patients chronically treated with the selective beta 1-adrenoceptor antagonists metoprolol or bisoprolol it was not different from control. It is concluded that beta-adrenoceptor antagonists without ISA increase human saphenous vein beta 2-adrenoceptors in a subtype-selective fashion.

β-adrenoceptor blocker treatment and the cardiac β-adrenoceptor-G-protein(s)-adenylyl cyclase system in chronic heart failure

“…NS β-Blocker patients treated with nonselective β-AR blocker propranolol and sotalol; β 1 -Blocker patients treated with the β 1 -AR selective blocker metoprolol, atenolol and bisoprolol. Modified from Michel et al (1988) and Brodde et al (1989) 1998). CHF patients show marked reduction in the positive force-frequency relationship (for references, see Just 1996) and no augmentation by β-AR stimulation (Bhargava et al 1998).…”

Comparison of the effects of nadolol and bisoprolol on the isoprenaline‐evoked dilatation of the dorsal hand vein in man

“…The human dorsal hand vein contains both band aadrenoceptors [1][2][3] and there is evidence that both a 1 -and a 2 -adrenoceptors mediate constrictor responses [3,4] and b 2 -adrenoceptors mediate dilator responses [3,5]. It is and nonselective adrenoceptor agonists.…”

“…The human dorsal hand vein contains both β‐ and α‐adrenoceptors [1‐3] and there is evidence that both α 1 ‐ and α 2 ‐adrenoceptors mediate constrictor responses [3, 4] and β 2 ‐adrenoceptors mediate dilator responses [3, 5]. It is more controversial, however, whether there are also venodilator β 1 ‐adrenoceptors in the dorsal hand vein.…”

The physiologic and histologic properties of the distal internal thoracic artery and its subdivisions

“…Nevertheless, He and colleagues 28 found only moderate arterial relaxation in response to isoproterenol (beta 1 and 2 adrenergic agonist) and concluded that betaadrenoreceptors would contribute little to the reactivity of the human ITA graft to sympathomimetic drugs. Brodde and colleagues 29 demonstrated the subtype-selective upregulation of beta-2 adrenergic receptors in the heart muscle and the SV by chronic beta-adrenoreceptor antagonist treatment. However, Ferro and colleagues 30 did not find a change in beta-1 or beta-2 reactions, or the alpha-1 adrenergic reaction in ITA and SV segments from patients chronically treated with beta-blockers.…”