[A study on the myocardial contractile function and intracellular free calcium in scalded rats].
OBJECTIVE
To explore the relationship between postburn myocardial function and intracellular free calcium concentration.


METHODS
Sprague-Dawley (SD) rats were employed as the model in which 7 were inflicted with 43% TBSA degree scalding (S group) and 7 as sham scalding control group (C group). The hearts of the injured rats were isolated and perfused in vitro by Langendorff method after 24 postburn hours (PBHs). The hearts were connected to a cardiac function monitor, and the dynamic changes in left ventricular develop pressure (LVDP) were continuously monitored. The cardiac 19F and 31P NMR spectroscopy was determined before and after and TF-BAPTA was added to the perfusate.


RESULTS
When compared with those in C group, the LVDP of scalded rat heart decreased by 40% (P < 0.01), and the myocardial cytoplasmic free calcium concentration was four times above that in C group (P < 0.01). After TF-BAPTA was taken by myocytes, cardiac LVDP only decreased by 15% to 20%, and the PCr/Pi ratio decreased, while there was no change in ATP.


CONCLUSIONS
Myocardial contractile function could be inhibited after burn injury, which might be related to the increase of myocardial cytoplasmic free calcium concentration.
Xia
Z
Z
Department of Burns, Changhai Hospital, Second Military Medical University, Shanghai 200433, P. R. China.
Tian
J
J
Tang
H
H
Wang
G
G
D000818:Animals; D002057:Burns, Chemical / Q000378:metabolism / Q000503:physiopathology*; D002118:Calcium / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism; D004195:Disease Models, Animal; D004734:Energy Metabolism; D006321:Heart / Q000503:physiopathology*; D009200:Myocardial Contraction / Q000502:physiology*; D009206:Myocardium / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D002118:Calcium