The Sound of Evolution
Methoxamine
Mechanism of action:
Methoxamine is a selective α₁-adrenergic agonist. Methoxamine binds to α₁ receptors on the surface of vascular smooth muscle cells in peripheral blood vessels, especially arterioles and veins. This activates the Gq protein signaling pathway, leading to activation of phospholipase Cβ, increased intracellular IP₃ and DAG, elevated cytosolic calcium concentration, and activation of protein kinase C, ultimately causing vascular smooth muscle contraction.
Reference(s):
1. Satoh M et al. (1994). Alpha 1-adrenoceptor subtypes mediating the regulation and modulation of Ca2+ sensitization in rabbit thoracic aorta. Eur J Pharmacol.
2. Suzuki E et al. (1990). Two pharmacologically distinct alpha 1-adrenoceptor subtypes in the contraction of rabbit aorta: each subtype couples with a different Ca2+ signalling mechanism and plays a different physiological role. Mol Pharmacol.