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G. ASHWELL, Z. DISCHE 



VOL. 4 (1950) 



were not investigated). M/ioo NagSO^ and Na phosphate, M/iooo K4Fe(CN)6 and M/90 

 KCNS which by themselves show little or no inhibition of aerobic glycolysis, strongly 

 inhibit in presence of M/250 MgClg, which by itself increases the glycolysis. The inhibi- 

 tion by M/4000 Ca in presence of M/ioo Na2S04 or Na phosphate is much stronger than 

 corresponds to the sum of inhibitions of the two kinds of ions (Table IV). This synergy 

 manifests itself also towards the oxidation of glucose as well as towards the original O2 

 consumption of the hemolysate. On the other hand no synergy was found between K 

 and Na2S04 or Na phosphate. 



/) Reversibility of the inhibitory effect of Ca against the aerobic glycolysis. That the 

 inhibition of the metabolism in the hemolysate by ions is not due to an irreversible 

 destruction of enzymes is clearly indicated by the fact that the degree of the inhibition 

 does not increase with the time even when the inhibition was not complete. The rever- 

 sibility of the inhibition was, furthermore, demonstrated directly for Ca in the following 

 way. Two samples of washed red cells were taken. One sample, hemolysate I, was 

 hemolyzed with 1.5 volumes of water containing enough Ca to yield a final concentration 

 of 2 mg % in the hemolysate. The other sample, hemolysate II, was hemolyzed with 

 1.5 volumes of water. 4 samples of i ml each were pipetted from every hemolysate. 

 0.03 ml of a 2% glucose solution were added to samples of hemolysate I and i sample of 

 hemolysate II (glucose samples) while to the remaining five samples 0.03 ml of water 

 was added (water samples). All samples were left for 2 hours at 25° and then the glucose 

 sample and one water sample of II and one of the glucose samples of I and one water 

 sample were deproteinized (2 hours samples). 0.6 ml of water was now added to the 

 glucose and water samples of I and to the one of the water samples of II while the other 

 water sample of II received 0.6 ml of a glucose solution of 0.1%. The Ca concentration 

 in I was thus reduced from 2 to 1.2 mg %. If the inhibition of the aerobic glycolysis 

 by Ca was reversible then the reduction of the Ca concentration in I should result in 

 a decrease of the inhibition in the following 2 hours. This was in fact the case. 



It must be noted that the 4 hour glucose sample of I contained more lactic acid 

 in the second 2 hour period than the corresponding sample of II. This tended to make 

 the inhibition by Ca rather stronger than weaker. 



TABLE VI 



BALANCE OF GLUCOSE CONSUMPTION, Oj UPTAKE AND LACTIC ACID FORMATION IN THE HEMOLYSATE. 



4 HOUR EXPERIMENTS AT 25° PH 7-0 



References p. 2g2. 



