VOL. 4 (1950) METABOLISM OF NUCLEATED RED CELLS • 29I 



siderable forces of repulsion on ions of the same charge and thus counteract their 

 adsorption. This repulsion will obviously be decreased by the simultaneous presence 

 in solution of ions of opposite charge of great surface activity. The adsorption of cations 

 will therefore be facilitated by the presence of easily adsorbable polyvalent anions, and 

 vice versa, and thus a higher degree of elimination of polarized groups on the protein 

 surface may be achieved. This again will affect the water binding capacity and the shape 

 of the respective protein molecule. 



This view appears supported by the rather striking analogy between the inhibition 

 of the aerobic metabolism by ions and the effect of certain ions on proteins like myosin, 

 actin, actomyosin and the so called structural proteins of kidney and brain investigated 

 by Szent-Gyorgyi and his associates'^. These proteins adsorb physiological cations 

 (Na, K, Ca, Mg) from solutions of physiological concentrations. Ca is more strongly 

 adsorbed than Mg and this again more strongly than the monovalent cations. This 

 adsorption neutralizes charges of polar groups on the protein surface and changes the 

 affinity to water and in the case of actin the ability to polymerize. A striking analogy 

 to the synergy between ions in our case can be seen in the influence of the cations 

 (K, Ca) on the adsorption of the polyvalent ATP ion by myosin. In this case the anion 

 of ATP does not counteract the effect of K on myosin but enhances it. 



The affinity of structural proteins to ions depends upon a certain specific state of 

 the protein surface and is easily suppressed by procedures tending to denature the 

 protein. The adsorption of cations by myosin for example decreases strongly during 

 24 hour storage at 0°'^. This may be the reason why such general inhibitory effects 

 of ions on oxidative enzymes have not yet been observed in tissue homogenates. In this 

 case the subcellular structural units may suffer considerable injury by the mechanical 

 crushing of the tissue. Hemolysis on the other hand appears as a much milder procedure 

 for getting access to a little altered inner parts of the cell. 



SUMMARY 



1. The hemolyzed nucleated erythrocytes of the pigeon show considerable Oj consumption, 

 which is considerably increased by MgClj M/250, glucose and constituents of the tricarboxylic acid 

 cycle and completely inhibited by NaCN M/250. 



2. This oxidative metabolism is coupled with a strong aerobic glycolysis. 



3. All multivalent cations and anions inhibit the Oj consumption as well as the aerobic glycolysis. 



4. CaClg, orthophosphate and ribonucleate inhibit strongly at physiological concentrations. 



5. Different oxidative reactions in the hemolysate are inhibited by ions to a different degree. 



6. These inhibitory effects of ions ma}^ be due to disturbances of the local electric fields of proteins 

 which are constituents either of membrane or stroma of subcellular structural units which are carriers 

 of enzymes of the oxidative system of the cell. 



RfiSUMfi 



1. Les nucleo-erythrocytes hemolyses du pigeon montrent une consommation d'oxygfene con- 

 siderable, qui est encore fortement accrue par MgClj M/250, le glucose et les constituants du cycle 

 des acides tricarboxyliques, mais completement inhibee par NaCN I\I/25o. 



2. Ce metabolisme d'oxydation est coupl6 avec une forte glycolyse aerobique. 



3. Tous les cations et anions plurivalents inhibent la consommation d'oxygene aussi bien que 

 la glycolyse aerobique. 



4. Le CaClj, I'ion orthophosphorique et I'ion ribonucleique sont de forts inhibiteurs aux con- 

 centrations physiologiques. 



5. Differentes reactions d'oxydation, dont I'h^molysat est le siege, sont inhibees par les ions a 

 des degrds diff^rents. 



6. Ces effects inhibitoires d'ions sont peut-etre dus a des perturbations des champs electriques 

 locaux des proteines qui sont des constituants soit de la membrane, soit du tissus conjonctif d'unites 

 structurales subcellulaires, supports d'enzymes du systeme d'oxydation de la cellule. 



References p. 2g2. 



