Efaroxan HCl (89197-00-2) is a selective α2-adrenergic receptor antagonist1 (selectivity ratio of α2/α1 = 724)4 and imidazoline receptor antagonist2. Induces release of insulin in the rat insulinoma cell line RIN-5AH by interaction with ATP-sensitive potassium channels independently from imidazoline I1 or I2 receptors.3 Efaroxan HCl increases resting plasma insulin levels and markedly potentiates the rise in insulin levels produced by adrenaline in the rat.4
Efaroxan Hydrochloride is a potent α2-AR adrenoceptor antagonist.
Potent, highly selective α 2 adrenoceptor antagonist and imidazoline I 1 receptor ligand (pK i values are 7.87, 7.42, 5.74, 7.28 and < 5 for α 2A , α 2B , α 2C , I 1 , and I 2 receptors respectively). Promotes insulin secretion, at a site distinct from I 1 or I 2 (the putative I 3 receptor) in vitro and in vivo .
1) Chapleo et al. (1984), alpha-Adrenoceptor reagents. 2. Effects of modification of the 1,4-benzodioxan ring system on alpha-adrenoceptor activity; J.Med.Chem., 27 570
2) Eglen et al. (1998), ‘Seeing through a glass darkly’: casting light on imidazoline ‘I’ sites; Trends Pharmacol. Sci., 19 381
3) Olmos et al. (1994), Imidazolines stimulate release of insulin from RIN-5AH cells independently from imidazoline I1 and I2 receptors; Eur. .J. Pharmacol., 262 41
4) Berridge et al. (1992), Comparison of the effects of efaroxan and glibenclamide on plasma glucose and insulin levels in rats; Eur. J. Pharmacol., 213 205
