Xestospongin C (88903-69-9) is a potent and reversible inhibitor of IP3-mediated Ca2+?release, IC50?= 358 nM.1?Experiments with guinea-pig ileum permeabilized with alpha toxin revealed that Xestospongin C inhibits the IP3 receptor but not the ryanodine receptor in SR membranes. In intact smooth muscle cells it inhibits voltage-dependent Ca2+?and K+?currents at a concentration range similar to that at which it inhibits the IP3 receptor. Xestospongin C is a useful tool for probing the involvement of IP3 receptors in cellular signaling.3?Cell permeable.
Xestospongin C is a potent, membrane-permeable IP3 receptor blocker.
Xestospongin C is a marine natural product which was first isolated from Pacific basin sponges, and noted to have vasodilatory properties. Xestospongin C antagonizes the calcium-releasing action of inositol-1,4,5-trisphosphate (IP3) at the receptor level. Inositol phosphates are important signal transduction messengers acting via IP3 receptors to promote the mobilization of Ca2+ from intracellular stores. Xestospongin C blocks the increase in intracellular calcium in vascular smooth muscle cells completely at a concentration of 25 μM. Xestospongin C also inhibits the sarcoplasmic reticulum Ca2+ ATPase pump at concentrations of 700 nM.
ChEBI: An organic heteropentacyclic compound that is isolated from the marine sponge Xestospongia exigua.
Synthetic form of the macrocyclic bis-1-oxaquinolizidine isolated from the Okanowan marine sponge.
Xestospongin C is a selective, reversible and membrane-permeable inhibitor of IP3 receptor. Reversibly blocks bradykinin- and carbamylcholine- Ca2+ efflux from the endoplasmic reticulum stores.
1) Wilcox?et al. (1998),?New developments in the molecular pharmacology of the myo-inositol 1,4,5-trisphosphate receptor;? Trends Pharmacol. Sci.,?19?467
2) Ozaki?et al. (2002),?Inhibitory mechanism of xestospongin-C on contraction and ion channels in the intestinal smooth muscle;? Br. J. Pharmacol.,?137?1207
3) Kandasamy?et al. (2013),?Lipopolysaccharide induces endoplasmic store Ca2+-dependent inflammatory responses in lung microvessels;? PLoS One,?8?e63465
