Effects of Curcumin on Parameters of Myocardial Oxidative Stress and of Mitochondrial Glutathione Turnover in Reoxygenation after 60 Minutes of Hypoxia in Isolated Perfused Working Guinea Pig Hearts

Figure 1

Parameters measured in preliminary experiments: (a) Afterload measured (red squares) during the course of 30 min of normoxia (about 100 cm water column) immediately dropped within 5 min of hypoxia to about 35 cm water column and then slowly decreased to zero between 10 and 25 min of hypoxia. In reoxygenation, afterload immediately improved again to 60 cm water column within 5 min and recovered to around 80 cm water column between 10 and 30 min of reoxygenation (red squares). To set up the “working” heart model, afterload was constantly set to 75 cm water column (blue diamond line). In subsequent experiments, the heart muscle had to pump against this pressure in its cardiac output (systolic phase). (b) Due to our model, aortic flow (red squares) was zero during hypoxia; it was around 20 mL/min in normoxia and recovered to about 10 mL/min (about 50% of normoxia) during the first 15 min of reoxygenation and then started to fluctuate and slowly decreased to almost zero by the end of experimental reoxygenation (R30). Coronary flow (blue diamonds) slowly decreased during normoxia and hypoxia from 35–40 mL/min to 3–5 mL/min by the end of hypoxia and then recovered rapidly to 30 mL/min in the beginning of reoxygenation and subsequently decreased slightly to 25 mL/min within 30 min of reoxygenation. (c) Systolic pressure (blue diamonds) was 90–100 mmHg in normoxia, dropped to 40 mmHg within 5 min of hypoxia, and further decreased to zero in 25 min of hypoxia. Within 5 min of reoxygenation, systolic pressure immediately recovered to 80–85 mmHg for 15 min and then started to fluctuate between 50 and 85 mmHg until the end of the experimental reoxygenation (R30). Diastolic pressure (red squares) showed similar course at a lower level with normoxic pressure of 55–75 mmHg, decreased to 20–25 mmHg in hypoxia, and dropped to zero after 20–25 min of hypoxia. Recovery during reoxygenation was stable between 35 and 45 mmHg until the end of experimental reoxygenation. These data in preliminary experiments served as the basis of setting up our model in subsequent main experiments with 60 min of hypoxia.

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