(R) -Terazosin

(R) -Terazosin is an active R-enantiomer of Terazosin. (R) -Terazosin is a potent antagonist of α1-adrenoceptor (α1a, α1b and α1d-adrenoceptor with Ki values of 6.51 nM, 1.01 nM and 1.97 nM, respectively) . (R) -Terazosin is low affinity for α2a, α2B and α2c-adrenoceptor (Ki of 3.85 μM, 0.33 μM and 0.37 μM, respectively) . (R) -Terazosin may prove to be a useful probe in understanding the functional role of subtypes of adrenoceptors in various tissues. (R) -Terazosin shows antagonism of at rat atrial α2B receptor (pEC30 : 5.69) . (R) -Terazosin shows antagonism of at rat vas deferens α1A and α2A receptor (pA2 of 7.5 and 5.31, respectively) . (In Vitro) : (R) -Terazosin is low affinity for α2a, α2B and α2c-adrenoceptor with Ki values of 3.85 μM, 0.33 μM and 0.37 μM, respectively. (R) -Terazosin may prove to be a useful probe in understanding the functional role of subtypes of adrenoceptors in various tissues. Because it is a weaker antagonist at α2B sites than its enantiomer, it may be possible to use (R) -Terazosin to differentiate between pharmacological effects mediated by subtypes of α2-adrenoceptors in animal studies. (In Vivo) : (R) -Terazosin shows antagonism of at rat atrial α2B receptor with a pEC30 of 5.69. (R) -Terazosin shows antagonism of at rat vas deferens α1A and α2A receptor with pA2 values of 7.5 and 5.31, respectively.