Send to

Choose Destination
Brain Res. 1981 Sep 28;221(2):307-18.

The calculation of the cytoplasmic free [NADP+]/[NADPH] ratio in brain: effect of electroconvulsive seizure.


This study has investigated the feasibility of calculating the cytoplasmic free [NADP+]/[NADPH] ratio in rat brain. The time course of the change in the substrate ratios of the malate dehydrogenase (decarboxylating) [E.C.], NADP+-isocitrate dehydrogenase (decarboxylating) [E.C.] and 6-phosphogluconate dehydrogenase (decarboxylating) [E.C.] reactions was followed for up to 10 min after a single, unmodified electroconvulsive seizure. From the results it has been concluded that during periods of low flux, the direction and magnitude of the change in the cytoplasmic free [NADP+]/[NADPH] ratio can, in fact, be reasonably determined even though there is some uncertainty in the absolute value of the ratio itself. It is recommended that reliance not be placed on a single enzyme system but that one or both of the other systems also be observed under a given experimental condition to increase confidence in the determination. The results also demonstrate that seizure and anoxia have a far lesser effect on the cytoplasmic free [NADP+]/[NADPH] ratio than on the free [NAD+]/[NADH] ratio in the same compartment. These results suggest that the pathways using the nicotinamide-adenine dinucleotide phosphate system are relatively protected from the rapid fluctuations that seizure and anoxia can produce.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center