An activator of Ca²⁺ release channel/ryanodine receptors.

33-mer basic peptide cross-linked by three disulphide bridges.
Synthetic‚ from Scorpio maurus palmatus scorpion venom.

Agonist of ryanodine receptor type 1‚ 2 and 3 - Potently and reversibly modifies channel gating behaviour of the type 1 ryanodine receptor (RyR1) by inducing increased opening probabilities and a prominent subconductance behaviour.

Binds to a different site than ryanodine.

Class of biological activity: Ca²⁺ channel activator.

At cellular level: Myotubes‚ HEK293 cells expressing RyR1.

Potency: EC₅₀ at 12 to 20 nM.

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