[Protective effects of dexamethasone on myocardium in rats with sepsis].
OBJECTIVE
To investigate the changes in heart function and myocardial mechanics in murine sepsis model, and the mechanism of the protective effect of dexamethasone on heart.


METHODS
Wistar rats were randomly divided into control group, lipopolysaccharide (LPS) group (4 mg/kg LPS intravenously), LPS+dexamethasone group (4 mg/kg LPS+2 mg/kg dexamethasone intravenously), with 32 rats in each group. A catheter was passed through right common carotid artery to the left cardiac ventricle. Function of the left ventricle was monitored, and blood was drawn at 0, 2, 4, 6 hours to detect concentrations of tumor necrosis factor-alpha (TNF-alpha), troponin T (TnT), with 8 rats for each time point.


RESULTS
In sepsis rats, TnT increased significantly and could be lowered by dexamethasone [at 6 hours after the treatment (1.76+/-0.57) microg/L vs. (0.70+/-0.36) microg/L, P<0.01]. There were changes in left ventricular peak systolic pressure (LVPP) and maximum rate of intraventricular pressure rise/down (+/-dp/dt max) to certain extent, and increase in left ventricular end-diastolic pressure (LVEDP), but these changes could be ameliorated by using dexamethasone. TNF-alpha increased significantly in sepsis rats, but dexamethasone could lower its level [at 2 hours after the treatment (11.22+/-2.38) pmol/L vs. (7.62+/-3.21) pmol/L, P<0.01].


CONCLUSIONS
Myocardium is remarkably damaged in rats with sepsis. TNF-alpha could be regarded as one of the factors which could produce injury to myocardium. Dexamethasone could alleviate cardiac damage produced by endotoxin in sepsis model.
Wang
Guo-xing
GX
Beijing Friendship Hospital, Capital University of Medical Science, Beijing 100050, China.
Shen
Lu-hua
LH
Xie
Miao-rong
MR
Jin
Ming
M
Long
Wei
W
Yin
Cheng-hong
CH
Zhang
Shu-wen
SW
D000818:Animals; D003907:Dexamethasone / Q000494:pharmacology*; D004195:Disease Models, Animal; D008297:Male; D009206:Myocardium / Q000473:pathology*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D018805:Sepsis / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D020107:Troponin T / Q000097:blood; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
D020107:Troponin T; D014409:Tumor Necrosis Factor-alpha; D003907:Dexamethasone