Table 2.

Measured and predicted CK flux and CK V_max and measured CK flux/V_max

	Measured CK Flux, mM/s	Predicted CK Flux, mM/s	CK Vmax, mM/s	Measured CK Flux/Vmax
Baseline
Control	8.1 ± 1.0	8.7	38.6 ± 1.8	0.21
CKM	32.9 ± 3.8	29.9	169.5 ± 10.8	0.17
At 40 min of reperfusion
Control	3.2 ± 0.4	1.8	17.4 ± 3.2	0.18
CKM	14.0 ± 1.2	12.9	159.4 ± 13.8	0.09

Values are means ± SE. The measured creatine kinase (CK) flux (in mM) is the rate of ATP synthesis through CK measured by ³¹P-magnetic resonance spectroscopy (MRS) in intact hearts. Predicted CK flux is the predicted rate of ATP synthesis through CK calculated from the CK rate reaction. CK V_max is the CK enzyme activity determined from heart extracts at 37°C (from Fig. 1C).