What is "ophanin"

Ophanin is a toxin found in the venom of the King Cobra ( Ophiophagus hannah), which lives throughout South East Asia. This toxin belongs to the cysteine-rich secretory protein (CRISP) family. Ophanin weakly blocks the contraction of smooth muscles elicited by high potassium-induced depolarization, suggesting that it inhibits voltage-dependent calcium channels.