Key result
Potency of alpha 2-adrenoceptor antagonists in human saphenous vein correlated significantly with affinity for the alpha 2B-ligand binding site (r = 0.71, P<0.01).
Effect estimate: r = 0.71
p-value: p=<0.01
The postjunctional alpha-2 adrenoceptor mediating contractions in the human saphenous vein resembles an alpha-2B subtype rather than an alpha-2A subtype.
Identifies alpha-2B-like adrenoceptors in human saphenous vein; leaves open subtype-selective antagonist development.
We have examined the effects of a series of alpha 2-adrenoceptor antagonists against isometric contractions to noradrenaline in human saphenous vein, and correlated these potencies with affinities for the alpha 2A-ligand binding site of human platelet and the alpha 2B-ligand binding site of rat kidney. 2. The alpha 2B-selective adrenoceptor antagonists, prazosin, ARC 239 and HV 723 showed high, and the alpha 2A-selective antagonist BRL 44408 showed low, potency in human saphenous vein. 3. Potency in human saphenous vein correlated better with affinity for the alpha 2B-ligand binding site (r = 0.71, n = 12, P less than 0.01) than with affinity for the alpha 2A-ligand binding site (r = 0.56, n = 12, non significant). 4. It is concluded that the postjunctional alpha 2-adrenoceptor of human saphenous vein resembles an alpha 2B-ligand binding site more than an alpha 2A-ligand binding site.
No takes yet. Share an insight, caveat, or question.
Smith et al. (1992) studied this question. alpha 2-adrenoceptor antagonists was evaluated on Correlation of potency in human saphenous vein with affinity for the alpha 2B-ligand binding site (r = 0.71, p=<0.01). Potency of alpha 2-adrenoceptor antagonists in human saphenous vein correlated significantly with affinity for the alpha 2B-ligand binding site (r = 0.71, P<0.01).
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: