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Related to calpain: cathepsin, calpastatin


A proteolytic enzyme regulated by the concentration of calcium ions.

[Probably cal(cium) + p(rote)a(se) + -in.]


any of various enzymes in mammals and other organisms that are involved in the proteolysis of endogenous proteins and are regulated by the concentration of calcium ions
[C20: from cal(modulin) + (pa)pain]
References in periodicals archive ?
By generating potent inhibitors to Calpain, Phelix is able to block the generation of myofibroblasts, the critical cell type in fibrosis.
43] AEP can cleave endogenous tau at Asn255 and Asn368 independently of caspases and calpains, generating neurotoxic fragments that form insoluble fibrils in vitro .
CaSR and calpain contribute to the ischemia reperfusion injury of spinal cord.
The increased intracellular calcium leads to (a) activation of the nitric oxide synthetase (NO) leading to cerebral edema and ischemia; (b) activation of casplases (destructive enzymes) that damage the DNA of the cell, leading to apoptosis; (c) activation of the proteases family of calpains, which cause the breakdown of the neuronal cytoskeleton leading to the loss of structural integrity of the neuron; (d) damage to the Na/K pump, leading to an influx of additional sodium followed by water with resultant cerebral edema; and (e) mitochondrial injury leading to reactive oxygen species generation, microvascular damage, and cerebral edema (Huh, Franklin, Widing, & Raghupathi, 2006; Robertson, Bucci, & Fiskum, 2004; Robertson, Saraswati, & Fiskum, 2007).
Oxidative environments decrease tenderization of beef steaks through inactivation of calpain.
Relationship between tenderising the levels of cathepsin B, cathepsin L, calpain I, calpain II, and AY-glucoronidaes.
15) In addition, the calcium-activated protease calpain inactivates certain but not all forms of the NCX of the neuron, contributing to the failure to maintain baseline Ca2 + concentrations.
Some chemical compounds already exist that block the activity of calpains, although the researchers do not yet know the exact function of calpain14, as very little has been published about it.
The calcium cations activate procaspase-3 and procaspase-8 [2] while the procaspase-8 activate calpain I ([mu]-calpain) [44].
Sustained calpain activation associated with lysosomal ruptura executes necrosis of postischemic CA1 neurons in primates.
2] Human genes: CAPN9, calpain 9; MLH1, mutL homolog 1; MSH2, mutS homolog 2; MSH6, mutS homolog 6; PMS2, PMS2 postmeiotic segregation increased 2 (S.
Chapter 3 considers the calpain family of proteolytic enzymes, and its role in muscle injury, ischemia/reperfusion and muscle atrophy.