[Noradrenaline dynamics in prolonged ischemia after ischemic preconditioning].
OBJECTIVE
To determine the effects of two-staged ischemic preconditioning on myocardial noradrenaline in prolonged ischemia and reperfusion.


METHODS
Thirty-two male Wistar rats anesthetised with urethane randomly divided into 2 groups: group 1 (ischemic preconditioning group, n = 16), and group 2 (control, n = 16). Myocardial interstitial noradrenaline levels were measured using a microdialysis technique. Ischemic preconditioning was elicited by two episodes: 5 min of ischemia and 10 min of reperfusion. The intermittent occlusions were followed by prolonged occlusion (60 min) and reperfusion (60 min).


RESULTS
An increase in interstitial noradrenaline was observed in 10 min of prolonged ischemia in group 2, and in 20 min in group 1. After 20 min of myocardial ischemia there was a significant difference between groups (p < 0.05) in interstitial noradrenaline levels. In control group, it was 60% higher. In reperfusion, noradrenaline levels decreased markedly in group 1.


CONCLUSIONS
We suggest that ischemic preconditioning by two episodes: 5-min ischemia and 10-min reperfusion prevents excessive noradrenaline interstitial accumulation, perhaps, through protection of physiological uptake I carrier.
Naumenko
S E
SE
Latysheva
T V
TV
Gilinskiĭ
M A
MA
D000818:Animals; D019157:Ischemic Preconditioning, Myocardial; D008297:Male; D017202:Myocardial Ischemia / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D009638:Norepinephrine / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D015424:Reperfusion; D013997:Time Factors
D009638:Norepinephrine