Ioppolo C, Currell D L, Civalleri L, Antonini E
Experientia. 1979 Aug 15;35(8):1112-3. doi: 10.1007/BF01949974.
The increase in methemoglobin reductase activity in human erythrocytes upon incubation with inosine, phosphate, pyruvate occurs only in the presence of methylene blue. No difference in activity of the methemoglobin reductases was observed between enzyme extracts of fresh cells and aged cells.