Nifedipine inhibits the activation of inflammatory and immune reactions in viral myocarditis

AimsThe aim of study is to investigate the effect of nifedipine on viral myocarditis in an animal model.Main methodsFour-week-old male DBA/2 mice were inoculated with 2 pfu of encephalomyocarditis virus (EMCV) and randomized to nifedipine (n = 10) or control (n = 10) group. The control group was fed by regular chow and the nifedipine group contained 0.01% of nifedipine. Mast cell density was counted, and expressions of messenger RNAs of stem cell factor (SCF), matrix metalloproteinases (MMPs), pro-collagen I, mast cell proteases, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) were evaluated by RT-PCR.Key findingsThe area of myocardial necrosis was smaller in the nifedipine vs the control group (mean ± SD, 1.2 ± 1.3% vs 3.8 ± 1.8%, respectively, P < 0.005). The mast cell density (count/mm2) was lower in the nifedipine vs the control group (mean ± SD, 0.23 ± 0.16 vs 1.08 ± 0.45, respectively, P < 0.0005). The expressions of MMPs, mast cell proteases, TNF-α, IL-6, SCF and pro-collagen I were lower in the nifedipine group than in the control group (P < 0.05).SignificanceNifedipine inhibited the activation of various participants in inflammatory and immune reactions in EMCV myocarditis.