Xestospongin C, Xestospongia sp.

A macrocyclic bis-1-oxaquinolizidine natural product isolated from a marine sponge. A very potent, reversible and membrane-permeable blocker of IP₃-mediated Ca²⁺ release (IC₅₀ = 358 nM) that does not interact with the IP₃-binding site. Displays high selectivity over the skeletal isoform of the ryanodine receptor type 1 (Ry₁R). Also blocks bradykinin- and carbamylcholine-induced Ca²⁺ efflux from the ER stores in a reversible manner.

An oxaquinolizidine alkaloid isolated from a marine sponge. A very potent, reversible, and membrane-permeable blocker of IP₃-mediated Ca²⁺ release (IC₅₀ = 358 nM) that does not interact with the IP₃-binding site. Displays high selectivity over the skeletal isoform of the ryanodine receptor type 1 (RyR-1). Also blocks bradykinin- and carbamylcholine-induced Ca²⁺ efflux from the endoplasmic reticulum stores in a reversible manner.

Primary Target
IP3-mediated Ca2+ release

Target IC₅₀: 358 nM in blocking IP3-mediated Ca2+ release

Toxicity: Harmful (C)

Sonication may be required to achieve complete solubilization.

Following reconstitution, aliquot and freeze (-20°C). Stock solutions are stable for up to 3 months at -20°C.

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