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Cyclopiazonic acid is a specific inhibitor of Ca2+-ATPase in the intracellular Ca2+ storage sites.
Cyclopiazonic acid is a Mycotoxin,
Cyclopiazonic acid formula: C20H20N2O3
Cyclopiazonic acid is produced by Penicillium cyclopium
Cyclopiazonic acid Molecular Weight : 336.39.
Cyclopiazonic acid Melting Point : 245 °C.
Cyclopiazonic acid is soluble in chloroform and DMSO.
Cyclopiazonic acid is sold as white to off-white hygroscopic powder.
Cyclopiazonic acid Chemical Name is (6aa,10z, 11ab, 11ba)-6a,7,11a,11b-tetrahydro-10-(1-hydroxyethylidene)-7,7- dimethyl-6H-pyrrolo [1',2':2,3]isoindolo [4,5,6-cd]indole-9,11 (2H,10H)-dione.
Cyclopiazonic acid Biological Activity :
CPA is a highly selective inhibitor of Ca2+ - ATPase in skeletal muscle sarcoplasmic reticulum .
stimulates release of Ca2+ from intracellular stores by increasing plasma membrane Ca2+ permeability without increasing intracellular inositol (1,4,5)-triphosphate levels. inhibits the Ca2+ uptake: by sarcoplasmic vesicles prepared from skeletal muscle , by intracellular stores sites caffeine-sensitive in guinea-pig smooth muscle cells (3µM) ; IC50 around 0.6 µM in skinned smooth muscle fibres of the longitudinal layer of the guinea-pig ileum .
causes selective and reversible strong suppression of Ca2+-dependent K+ current in guinea-pig ileal and urinary bladder smooth muscle cells. It is effective in intact cells and can be washed out .
Its mechanism of action may be the following: decreases Ca2+ uptake by the inhibition of Ca2+ -pump in the sarcoplasmic and endoplasmic reticulum, decreases the subsequent Ca2+ release from these storage sites and, thereby, reduces the Ca2+ dependent K+ current .
Cyclopiazonic acid Toxicity (LD50) in rat (orally): 36 mg/kg;.
Cyclopiazonic acidStorage recommendations : it is stable in dry state, store at +4°C, avoiding humidity.
Interaction of cyclopiazonic acid with rat skeletal muscle sarcoplasmic reticulum vesicles. Effect on Ca2+ binding and Ca2+ permeability.
Toxicological evaluations of cyclopiazonic acid and ochratoxin A in broilers.
Age and growth-related changes in cyclopiazonic acid-potentiated lipophilic cation accumulation by cultured cells and binding to freeze-thaw lysed cells
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