Respiratory defect as an early event in preservation-reoxygenation injury of endothelial cells.

摘要: Characterization of preservation injury in endothelial cells has been primarily accomplished by measurement cell viability. To analyze early events and cellular mechanisms preservation-reoxygenation injury, we developed high-resolution respirometry for the study mitochondrial function cells, to provide a quantitative marker sublethal stress. Cultured human umbilical vein were stored 4 8 hr at degrees C under an atmosphere 95% N2 5% CO2 University Wisconsin (UW) histidine-tryptophan-ketoglutarate (HTK) solutions. Respiration suspended measured after reoxygenation growth medium 37 C, was significantly reduced all treatments comparison controls not subjected cold preservation. In contrast, trypan blue staining unchanged significant only hr. After storage UW HTK solutions, respiration 64+/-5% 49+/-6%, respectively, (46.5+/-3.3 pmol O2 x s(-1 10(-6) cells), indicating better protection solution than solution. A titration regimen with substrate (succinate), uncoupler (carbonyl cyanide p-trifluoromethoxyphenylhydrazone), inhibitors complexes I III (rotenone antimycin A) resulted identical respiratory response patterns treatments. The plasma membrane remained impermeable succinate. Inner preserved as indicated constant relative increase uncoupling. These results demonstrate that loss catalytic capacity constitutes event whereas damage is primary defect. Respirometric evaluation localization may selective guidelines further optimization strategies organ