OBJECTIVETo investigate the inhibitor of matrix metalloproteinase-2 (MMP-2) (2R)-2-[5-[4-[ ethyl-methylamino] phenyl [thiophene-2-sulfonylamino]-3-methylbutyric acid (TISAM) therapeutic effect on experimental autoimmune myocarditis (EAM) in Lewis rats.

METHODSTreatment protocol of oral administration of 5 mg/kg TISAM once a day for 14 days was performed on EAM Lewis rats. EAM Lewis rats were divided into 3 groups: treatment in early, middle and later stage respectively (n = 20). After experiment at the designate time point, the rats were euthanatized and hearts were harvested. Cardiac inflammatory score, fibrosis score and content, and infiltration of macrophages and T lyminflammatory score, fibrosis score and content, and infiltration of macrophages and T lymphocytes, message RNA (mRNA) expression of matrix metalloproteinase (MMP)-2 and MMP-9 and protein activity of gelatinase were determined.

RESULTSTISAM treatment in early phase was invalid (treatment started from the creation of the model), treatment in middle and later phase was effective (treatment started from 7 and 14 day after the creation of the model).

CONCLUSIONInhibitor of MMP-2 can block ventricular remodeling in middle stage in EAM Lewis rats. The mechanism maybe alleviate the inflammatory cell cardiac infiltration, decrease the mRNA expression of MMP-2 at transcript level and downregulate gelatinase activity at protein level.