[Effects of angiotensin-(1-7) on remodeling of myocardial collagen network in pressure-overloaded rats].
OBJECTIVE
To investigate the effects of angiotensin-(1-7) on remodeling of myocardial collagen network in pressure-overloaded rats.


METHODS
A rat model of pressure-overloaded heart was induced by constriction of abdominal aorta. Seventy-five male Sprague Dawley rats were randomized to sham-operated group, model control group and angiotensin-(1-7) group. The rats of the latter two groups were treated with intravenous infusion of either angiotensin-(1-7) (25 microg x kg(-1) x h(-1)) or saline after operation. Ratio of left ventricular weight to body weight (LVW/BW) and myocardial collagen volume fraction (CVF) were determined at 1 and 4 weeks after operation. And types I and III collagen mRNA expressions were assessed with reverse transcription-polymerase chain reaction (RT-PCR).


RESULTS
At 1 week after the operation, types I and III collagen mRNA expressions of the left ventricular myocardium in model group and angiotensin-(1-7) group were increased significantly compared with those in sham-operated group. But those in angiotensin-(1-7) group were significantly lower than that in model group. At 4 weeks after the operation, LVW/BW and CVF were increased significantly in model group and angiotension-(1-7) group compared with those in sham-operated group, but those in angiotension-(1-7) group were significantly lower than that of model group.


CONCLUSIONS
Angiotensin -(1-7) can attenuate remodeling of myocardial collagen network in pressure-overloaded rats.
He
Jian-gui
JG
Department of Cardiology, First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, Guangdong, China. hejiangui@163.com
Huang
Yi-yi
YY
Ma
Hong
H
He
Xiao-hong
XH
Liao
Xin-xue
XX
Wang
Li-chun
LC
Zhou
Jian-zhong
JZ
D000809:Angiotensins / Q000494:pharmacology*; D000818:Animals; D003094:Collagen / Q000378:metabolism*; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D020257:Ventricular Remodeling / Q000187:drug effects*
D000809:Angiotensins; D012333:RNA, Messenger; D003094:Collagen