Extent of damage in ischemic, nonreperfused, and reperfused myocardium of anesthetized rats.
To investigate the localization of the earliest damage in ischemic and ischemic-reperfused myocardium, anesthetized rats were subjected to coronary occlusion for 15, 30, 45, or 90 min. One-half of the animals in each group had no reperfusion, whereas the other half was reperfused for 14 min. With the use of histological methods, preferentially in the periphery of the area at risk, localized zones were detected that lacked the hypoxia-specific increase in NADH fluorescence. The extent of these areas displaying injured tissue was found to be significantly smaller in the ischemic-nonreperfused hearts than in the ischemic-reperfused organs (15-min ischemia: 0.22 +/- 0.12% vs. 43.0 +/- 5.0%; 30-min ischemia: 5.7 +/- 2.7% vs. 64.6 +/- 2.9%; 45-min ischemia: 5.6 +/- 1.2% vs. 66.0 +/- 7.5%; 90-min ischemia: 39.3 +/- 5.5% vs. 86.7 +/- 1.8% of the area at risk). The results point to a localized initiation of the damage close to the surrounding oxygen-supplied tissue during ischemia and an expansion of this injury by intercellular actions into yet-intact areas upon reperfusion.
Zentrum Anaesthesiologie, Abteilung Anaesthesiologische Forschung, Universität Göttingen, Robert-Koch-Strasse 40, Robert-Koch-Strasse 40, D-37075 Göttingen, Germany. fvetterl@med.uni-goettingen.de
Friedrich
F
Vetterlein
Christina
C
Schrader
Rolf
R
Volkmann
Marion
M
Neckel
Matthias
M
Ochs
Gerhard
G
Schmidt
Gerhard
G
Hellige
D000758:Anesthesia; D000818:Animals; D005260:Female; D005453:Fluorescence; D008854:Microscopy, Electron; D017202:Myocardial Ischemia / Q000473:pathology*; D015428:Myocardial Reperfusion Injury / Q000473:pathology*; D009206:Myocardium / Q000737:chemistry / Q000473:pathology*; D032383:Myocytes, Cardiac / Q000737:chemistry / Q000473:pathology / Q000648:ultrastructure; D009243:NAD / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D013778:Tetrazolium Salts
C094100:2,2'-di-4-nitrophenyl-5,5'-diphenyl-3,3'-(3,3'-dimethoxy-4,4'-diphenylene)ditetrazolium; D013778:Tetrazolium Salts; D009243:NAD