[Age-dependent differences of the ultrastructural changes in the myocardium after hypoxical preconditioning and ischemia-reperfusion of the isolated heart in rats].
Recently we evidenced the ability of acute systemic hypoxia to induce phenomenon of delayed cardioprotection in rats. Age-dependent peculiarities were studied in 6 and 12 month old rats exposed to hypoxical preconditioning (10% O2, 1 or 3 h). In 24 h isolated hearts were ischemized 30 min and then reperfuzed 40 min, with or without iNOS blocker 1,3-PBIT (50 nmol/l). It was shown that hypoxic preconditioning dose-dependently injured myocardial ultrastructure, and induced delayed cardioprotection, strongly marked after 3 h preconditioning. Blockade of iNOS as mediator of delayed cardioprotection led to mitochondrial stimulation and attenuated protection. In mature aged rats, myocardial injury and protection had been individually variable, mitochondria were more damaged and stimulated to biogenesis, and incomplete autophagy was typical as distinct from young rats.
Portnychenko
A H
AH
Rozova
K V
KV
Vasylenko
M I
MI
Moĭbenko
O O
OO
D000222:Adaptation, Physiological; D000375:Aging / Q000473:pathology*; D000818:Animals; D000860:Hypoxia / Q000503:physiopathology*; D066298:In Vitro Techniques; D008297:Male; D008854:Microscopy, Electron; D008929:Mitochondria, Heart / Q000648:ultrastructure; D015428:Myocardial Reperfusion Injury / Q000473:pathology / Q000517:prevention & control; D009206:Myocardium / Q000648:ultrastructure*; D051381:Rats; D017208:Rats, Wistar