Chronic use of low dose simvastatin does not alter the IVCT in normal rats

Background Statins are currently the preferred agent for the treatment of hypercholesterolemia. However, myalgia, increased serum levels of creatinekinase (CK) and even rhabdomyolysis may occur, characterizing the cholesterol lowering agents myopathy (CLAM), with a multifactorial aetiology. In statin monotherapy, the incidence of CLAM is 0.1 to 0.5 % and is dose related. RYR1 (ryanodine 1) gene alteration was observed in the patients with CLAM, an animal model of MH (malignant hyperthermia) showed hyper metabolism after simvastatin, simvastatin induced in vitro contractures in muscle of animal model and susceptibility to MH by IVCT (in vitro contracture test) was diagnosed in patients with CLAM. On the other way, postoperative rhabdomyolysis occurred in patients treated with cholesterol-lowering drugs, leading to the suggestion of suspend these medications prior to surgery or do not use succinylcholine in patients taking these drugs . But this stance is challenged by other groups. Thus, this study examined, in rats chronically exposed to simvastatin dose previously associated with muscle alteration, the outcome of the IVCT.