Pe. Meyer et al., Effects of storage and reperfusion oxygen content on substrate metabolism in the isolated rat lung, ANN THORAC, 70(1), 2000, pp. 264-269
Citations number
17
Categorie Soggetti
Cardiovascular & Respiratory Systems","Medical Research Diagnosis & Treatment
Background. Lung transplantation requires a period of storage and ischemia;
we examined the largely unknown effects of that period on intermediary met
abolism.
Methods. Two groups of isolated rat lung blocks (n = 16 each) were flushed
with Euro-Collins solution and harvested. The lung blocks were immediately
ventilated and either perfused for 30 minutes with an erythrocyte-based sol
ution containing carbon 13 labeled substrates (group 1) or stored for 6 hou
rs at 1 degrees C and then reperfused (group 2). Half of each group was rep
erfused at a physiologic Po-2 the other half at high Po-2. Analysis of carb
on 13 isotopomers was performed to determine substrate utilization through
aerobic pathways in lung tissue.
Results. Lungs from both groups oxidized all major substrates. The contribu
tion of fatty acids to acetyl-coenzyme acid oxidized in the citric acid cyc
le was significantly higher in group 2 than in group 1 (31.3% +/- 2.2% vers
us 22.0% +/- 2.1%, p < 0.05). Perfusate Po-2 did not affect substrate prefe
rence. Gas exchange was worse in stored lungs.
Conclusions. After a period of hypothermic ischemia and storage, substrate
preference in lung tissue exhibits a switch towards fatty acids. As fatty a
cid oxidation occurring after ischemia is deleterious in other organs, stra
tegies to inhibit this process in stored lungs may warrant further investig
ation. (Ann Thorac Surg 2000;70:264-9) (C) 2000 by The Society of Thoracic
Surgeons.