Description
An alkaloid with vasoconstrictor and metabolic activities; binds to α1A-, α2A-, and α2C-adrenergic receptors (ARs; Kis = 78, 36.7, and 24.4 µM, respectively); an agonist of α1A-ARs in HEK293 cells (EC50 = 4 µM) but not in CHO cells expressing α2A- or α2C-AR; acts as an antagonist of α1A-, α2A-, and α2C-ARs, inhibiting L-phenylephrine-induced activation of α1A-AR in HEK293 cells and medetomidine-induced activation of α2A- and α2C-ARs in CHO cells (IC50s = 12.8, 26, and 27.3 µM, respectively); induces contractions in isolated rabbit aortic rings (EC50 = 6.2 µg/ml) and increases ligation-induced mean arterial pressure in rats at 2 mg/kg per day; induces lipolysis in isolated rat and human adipocytes when used at 100 and 1,000 µg/ml; increases phosphorylation of Akt and AMPK and translocation of Glut4 to the plasma membrane at 50 µM; increases insulin-induced glucose consumption in L6 muscle cells when used at 25-200 µM