Ryanodine

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Ryanodine
Identifiers
CAS number [15662-33-6]
PubChem 5114
MeSH Ryanodine
Properties
Molecular formula C25H35NO9
Molar mass 493.547 g/mol
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Ryanodine is a poisonous alkaloid found in the South American plant Ryania speciosa (Flacourtiaceae). It was originally used as an insecticide.

The compound has extremely high affinity to the ryanodine receptor, a group of calcium channels found in skeletal and heart muscle cells. It binds with such high affinity to the receptor that it was used as a label for the first purification of that class of ion channels and gave its name to it.

At nanomolar concentrations, ryanodine locks the receptor in a half-open state, whereas it fully closes them at micromolar concentration. The effect of the nanomolar-level binding is that ryanodine causes release of calcium from calcium stores in the sarcoplasmic reticulum leading to massive muscular contractions.

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