Figure 4.

APoC prevents rapid pH_m recovery in cardiomyocytes at reoxygenation. (A) Representative images showing selective mitochondrial loading of SNARF-1. SNARF-1 colocalizes with mitochondrial flavoproteins (FP). (B) pH_m decreased during hypoxia as shown by a decrease in SNARF-1 ratio. Upon reoxygenation, pH_m quickly recoverd to baseline levels. Treatment of cardiomyocytes with isoflurane at the beginning of reoxygenation preserved acidic intracellular pH_m during reoxygenation as compared with the control group. (C) The panel shows representative time lapse of baseline pH_m recording. Baseline pH_m was reduced upon addition of isoflurane into superfusing solution, and this effect was reversible after anaesthetic washout. (D) Administration of the mitochondrial uncoupler 2-4-dinitrophenol (DNP) prevented any further effect of isoflurane on pH_m. Data are presented as means ± standard deviation, *P < 0.05 versus APoC; n= 20. APoC, isoflurane postconditioning; SNARF-1, 5-(and-6)-carboxy SNARF-1, acetoxymethyl ester.