Ryanodine
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Ryanodine | |
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Identifiers | |
CAS number | [15662-33-6] |
PubChem | |
MeSH | |
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.
[edit] References
- Bertil Hille, Ionic Channels of Excitable Membranes, 2nd edition, Sinauer Associates, Sunderland, MA, 01375, ISBN 0-87893-323-9