Ryanodine

Ryanodine

Ryanodine
Names
IUPAC name
(1R,2R,3S,6S,7S,9S,10R,11S,12R,13S,14R)-2,6,9,11,13,14-Hexahydroxy-11-isopropyl-3,7,10-trimethyl-15-oxapentacyclo [7.5.1.01,6.07,13.010,14]pentadec-12-yl 1H-pyrrole-2-carboxylate
Identifiers
 YesY
ChEBI  YesY
ChEMBL  N
ChemSpider  YesY
Jmol-3D images Image
KEGG  N
MeSH
PubChem
Properties
C25H35NO9
Molar mass 493.547 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
 N  (: YesY/N?)

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

The compound has extremely high affinity to the open-form ryanodine receptor, a group of calcium channels found in skeletal muscle, smooth muscle, 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 as the sarcoplasmic reticulum in the cytoplasm, leading to massive muscular contractions. The effect of micromolar-level binding is paralysis. This is true for both mammals and insects.

See also

  • Ryanoid, a class of insecticides with the same mechanism of action as ryanodine

References

  • Bertil Hille, Ionic Channels of Excitable Membranes, 2nd edition, Sinauer Associates, Sunderland, MA, 01375, ISBN 0-87893-323-9