[Cardiac mast cells accumulation and degranulation contribute to collagen deposition after coronary microembolization].
To investigate potential pathophysiological role of cardiac mast cells accumulation and degranulation on the collagen deposition after coronary microembolization (CME).



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.



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.



MCs accumulation and degranulating contribute to myocardial fibrosis collagen deposition.
Zhang
Qing-yong
QY
Department of Cardiology, The No.6 People's Hospital, Shanghai Jiaotong University, Shanghai 200233, China. yeakcardio@yahoo.com.cn
Wang
Zhi-hua
ZH
Li
Xiao-bo
XB
Yin
Lian-hua
LH
Li
Jing-bo
JB
Wei
Meng
M
D000818:Animals; D015550:Cell Degranulation; D003094:Collagen / Q000378:metabolism*; D003331:Coronary Vessels / Q000473:pathology* / Q000503:physiopathology; D004617:Embolism / Q000473:pathology* / Q000503:physiopathology; D008407:Mast Cells / Q000473:pathology / Q000502:physiology*; D009206:Myocardium / Q000378:metabolism / Q000473:pathology*; D013552:Swine; D013556:Swine, Miniature
D003094:Collagen