Are diabetic hearts more resistant to ischemia/reperfusion injury?
The present study was designed to investigate the cardiac impairment during ischemia/reperfusion injury in rats with streptozotocin-induced diabetes vs controls. Male rats were divided into three groups: controls, one-week diabetic rats (1wDM) and four-week diabetic rats (4wDM). In the isolated working heart, left ventricular developed pressure (LVDP), left ventricular end-diastolic pressure (LVEDP), and maximum positive and negative dP/dt were measured before ischemia and after 20 min of global ischemia followed by 30 min reperfusion. In the pre-ischemic state, hearts of 4wDM showed a significant (p < 0.05) depression of the maximum positive and negative dP/dt compared with those of controls and 1wDM. There were no significant differences in LVDP and LVEDP among the three groups. The incidence of reperfusion-induced ventricular fibrillation (VF) was 75% for controls, 15% for 1wDM rats, and 27% for 4wDM rats. In hearts without reperfusion-induced VF, there were no differences in the three groups, between the pre- and post-ischemic values in LVDP, LVEDP, and maximum positive and negative dP/dt. These findings suggest that diabetic hearts exhibit no susceptibility to ischemia/reperfusion injury.
Third Department of Internal Medicine, Nagoya University School of Medicine, Japan.
O
O
Suzuki
T
T
Matsubara
M
M
Kanashiro
M
M
Nakao
R
R
Terada
H
H
Nishimura
K
K
Haruta
T
T
Ikeda
N
N
Sakamoto
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology*; D004198:Disease Susceptibility; D006439:Hemodynamics; D008297:Male; D017202:Myocardial Ischemia / Q000503:physiopathology*; D015428:Myocardial Reperfusion Injury / Q000503:physiopathology*; D051381:Rats; D017208:Rats, Wistar; D014693:Ventricular Fibrillation / Q000503:physiopathology; D016277:Ventricular Function, Left