Acidic and basic fibroblast growth factors involved in cardiac angiogenesis following infarction.
Acidic and basic fibroblast growth factors (FGF-1/FGF-2) promote angiogenesis in cancer. Angiogenesis is integral to cardiac repair following myocardial infarction (MI). The potential regulation of FGF-1/FGF-2 in cardiac angiogenesis postMI remains unexplored. Herein, we examined the temporal and spatial expression of FGF-1/FGF-2 and FGF receptors (FGFR) in the infarcted rat heart at days 1, 3, 7, and 14 postMI. FGF-1/-2 gene and protein expression, cells expressing FGF-1/-2 and FGFR expression were examined by quantitative in situ hybridization, RT-PCR; western blot, immunohistochemistry and quantitative in vitro autoradiography. Compared to the normal heart, we found that in the border zone and infarcted myocardium 1) FGF-1 gene expression was increased in the first week postMI and returned to control levels at week 2; FGF-1 protein levels were, however, largely reduced at day 1, then elevated at day 3 peaked at day 7 and declined at day 14; and cells expressing FGF-1 were primarily inflammatory cells; 2) FGF-2 gene expression was significantly elevated from day 1 to day 14; the increase in FGF-2 protein level was most evident at day 7 and cells expressing FGF-2 were primarily endothelial cells; 3) FGFR expression started to increase at day 3 and remained elevated thereafter; and 4) FGF-1/FGF-2 and FGFR expression remained unchanged in the noninfarcted myocardium. Thus, FGF-1/FGF-2 and FGFR expression are enhanced in the infarcted myocardium in the early stage after MI, which is spatially and temporally coincident with angiogenesis, suggesting that FGF-1/FGF-2 are involved in regulating cardiac angiogenesis and repair.
Zhao
Tieqiang
T
Division of Cardiovascular Diseases, Department of Medicine, University of Tennessee Health Science Center, 956 Court Ave., Rm B324, Memphis, TN 38163, United States.
Zhao
Wenyuan
W
Chen
Yuanjian
Y
Ahokas
Robert A
RA
Sun
Yao
Y
D000818:Animals; D016220:Fibroblast Growth Factor 1 / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D016222:Fibroblast Growth Factor 2 / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D008297:Male; D009203:Myocardial Infarction / Q000378:metabolism* / Q000473:pathology; D009389:Neovascularization, Pathologic / Q000378:metabolism* / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley
D016222:Fibroblast Growth Factor 2; D016220:Fibroblast Growth Factor 1