[Protective effects of taurine on myocardial injury in severely burned rats].
OBJECTIVE
To investigate the effect of taurine on myocardial injury in severely scalded rats.


METHODS
A total of 130 healthy adult Wistar rats were randomly divided into 3 groups: the control group (C, without burns), the burn group (B, subjected to a 30% TBSA III degree scalding) and the treatment group (T, treated with intraperitoneal injection of taurine (400 mg/kg) immediately after scald injury). The plasma and myocardial tissue samples in B and T groups were harvested at 1, 3, 6, 12, 24 and 48 postburn hours (PBH) for the determination of the contents of cardiac troponin T (cTnT), malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-alpha), and angiotensin II (AngII) in plasma, and the contents of TNF-alpha, AngII and calcium ion in myocardial tissue. The morphological change in the myocardial tissue was observed with transmission electronic microscope (TEM) and was compared with that in C group. The changes in the plasma TNF-alpha and AngII were analyzed in relation to that of plasma cTnT.


RESULTS
The plasma cTnT content in B group at 3 PBH was markedly higher than that in C group (0.16 +/- 0.03 microg/L) (P < 0.01), and it peaked (6.32 +/- 0.41) at 12 PBH and remained at high level at 48 PBH. While the plasma MDA content and the calcium ion level in B group were evidently higher than those in C group during 3 to 48 PBH (P < 0.01). The TNF-alpha contents in plasma and myocardial tissue during 6 to 48 PBH were significantly higher than those in C group (P < 0.01). The AngII contents in plasma and myocardial tissue during 3 to 24 PBH were obviously higher than those in C group (P < 0.01). All the indices in T group were significantly lower than those in B group (P < 0.01). Histological examination revealed that there was myocardial damage in various degrees during early postburn stage in B group, such as focal dissolution and fragmentation of myofilament, mitochondrial edema, myocyte sarcoplasmic protrusions like piano keys. But all the above changes in T group were evidently ameliorated to near normal. There was close positive correlation between the change in the concentrations of plasma content of TNF-alpha and AngII and cTnT in B group (r = 0.87 and 0.82, P < 0.05).


CONCLUSIONS
The production of TNF-alpha, MDA, cTnT, AngII and high calcium ion level of myocardiocytes in severely burned rats can be inhibited by taurine, which was beneficial in the management of myocardial injury after severe burns.
Wan
Fu-sheng
FS
Department of Biochemistry and Molecular Biology, Jiangxi Medical College, Nanchang 330006, P.R. China.
Li
Guo-hui
GH
D000804:Angiotensin II / Q000096:biosynthesis; D000818:Animals; D002056:Burns / Q000188:drug therapy* / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism* / Q000648:ultrastructure; D051381:Rats; D017208:Rats, Wistar; D013654:Taurine / Q000627:therapeutic use*; D020107:Troponin T / Q000096:biosynthesis; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
D020107:Troponin T; D014409:Tumor Necrosis Factor-alpha; D000804:Angiotensin II; D013654:Taurine; D008315:Malondialdehyde; D002118:Calcium