Cardiac mast cells accumulation and degranulation contribute to collagen deposition after coronary microembolization / 浙江大学学报·医学版

ABSTRACT

<p><b>OBJECTIVE</b>To investigate potential pathophysiological role of cardiac mast cells accumulation and degranulation on the collagen deposition after coronary microembolization (CME).</p><p><b>METHODS</b>CME was induced in miniswine by selective infusion of 15X10(4) microspheres (diameter, 45 mum) into the left anterior descending artery groups (CME group, n=8). Some CME-induced animals were pretreated with the MC stabilizer tranilast (50 mg/kg, twice daily), beginning 2 weeks before CME and thereafter throughout the experimental period (CME +tranilast group, n=8), while some animals received tranilast without CME (tranilast group, n=8). Eight sham-operated animals without CME served as controls. After 30 days, the total number of MC and degranulating MCs and collagen deposition was assessed by histological and electronic microscopy studies.</p><p><b>RESULTS</b>The numbers of total and degranulating MCs and collagen volume fraction (CVF) at day 30 in CME group were significantly higher than those in controls (P <0.01). Treatment with tranilast significantly reduced the numbers of total and degranulating MCs and CVF at day 30 (all P <0.01). There was a significant positive correlation of the CVF with the number of total MCs (r=0.91, P <0.001) and degranulating MCs (r=0.92, P <0.001) over the CME myocardium.</p><p><b>CONCLUSION</b>MCs accumulation and degranulating contribute to myocardial fibrosis collagen deposition.</p>