284 G. ASHWELL, Z. DISCHE VOL. 4 (1950) 



tion in the hemolysate as well as the additional uptake in presence of glucose and the 

 dicarboxylic acids. The increase ranges from 18 to 24% for the basic respiration and 

 from 67 to 88% for the additional respiration due to glucose (Table I). At the same 

 time there is an increase of the aerobic-glycolysis amounting to 21-46% of the original 

 value (Table I, Exp. I-III). This effect of Mg reaches its maximum at M/200 to M/150. 

 The additional O2 uptake as well as the accompanying aerobic glycolysis are inhibited 

 by M/500 NaCN to the same extent as is the case without addition of Mg. 



b) Univalent cations. When so much KCl is added to the hemolysate that the con- 

 centration of the added salt in the hemolysate becomes i/ii M and the hemolysate 

 therefore isotonic no inhibition of the basic O2 uptake with and without glucose can be 

 observed. The aerobic glycolysis is in general somewhat decreased. In some cases, how- 

 ever, a decrease of 60% was observed. NaCl at the same concentration decreases 

 the O2 uptake moderately and inhibits the aerobic glycolysis 33-50%. It must be 

 noted that this concentration of Na ions cannot be considered any more as physiological. 

 If the concentration of the added NaCl was only M/25 no significant inhibition of the O2 

 uptake or aerobic glycolysis could be observed. These observations indicate that CI ions 

 in physiological concentrations do not have any significant effect on the aerobic meta- 

 bolism of the hemolysate. 



c) Calcium and other multivalent cations. When the concentration of Mg exceeds 

 M/150 the aerobic glycolysis in the hemolysate begins te decline. At M/80 an inhibition 

 of about 15-25% appears. This inhibitory effect is a property of all multivalent cations. 

 (Table IV). Of all the cations investigated Ca shows the strongest inhibitory effect. 

 M/i ooo-M/i 500 shows almost complete inhibition of the aerobic glycolysis. Sr is almost 

 as strong but Ba++, Ce+++ and La+++ are ten times weaker inhibitors. However, our 

 figures merely correlate the strength of the inhibition with the overall concentration 

 of the salt. The latter is almost identical with the concentration of the bivalent ions for 

 the earth alkalis and rare earth but not for the other metals, the hydroxides of which 

 possess low second dissociation constants. The ion Mn++ and Cd++ as such are, therefore, 

 probably stronger inhibitors than Ca++. This however does not seem of any physiological 

 significance. The inhibitory effect of Ca on the glycolysis is still perceptible at M/8000. 

 After having ascertained that the inhibitory effect of Mg and Ca on glycolysis is related 

 to their multivalence the effects on the O2 consumption of those two as representatives 

 of multivalent cations were studied. The basic O2 consumption was inhibited 28-52% 

 by Ca M/iooo. The oxidation due to glucose, however, may completely disappear at 

 this concentration while that of succinate and a-ketoglutarate is reduced to about the 

 same extent as the basic respiration (Table III). 



d) Anions. All multivalent anions inhibit strongly the aerobic glycolysis (Table III). 

 The importance of valency is more marked with anions than cations. The bivalent 

 HPO4 — and SO4 — show a significant inhibition only at M/ioo and M/50 respectively, 



while the tetravalent Fe(CN) at M/250, ribonucleate, diphosphoglycerate and ino- 



sitolhexaphosphate strongly at M/1500, M/700 and M/iooo respectively. The nature 

 of the ion plays, however, also a considerable role. The bivalent oxalate for example 

 shows at M/iooo a stronger inhibition than malonate at M/200. The physiological 

 polycarboxylic acids like succinate and citrate, which up to M/500 increase the aerobic 

 glycolysis, inhibit at higher concentrations. At M/50 the inhibition is considerable with 

 citrate. That multivalency is only one of the factors promoting the inhibitory effect 

 on the metabolism is shown by the behaviour of the CNS~ ion. While KCl at M/ii and 

 References p. 2g2. 



