SUBSTRATES OTHER THAN SUCCINATE 



109 



Table 1-22 



Urinary Excretion of Citrate Following Administration of the Sodium Salts 



OF Various Weak Acids 



Substance 



Urinary citrate " after dose '' of : 



4.35 



26 



26 



39 



None 



NaCl 



NaHCOg 



Malonate 



Succinate 



Pyruvate 



a-Ketoglutarate 



Fumarate 



Malate 



Oxalacetate 



Glutarate 



Adipate 



Maleate 



Acetate 



Citrate 



Aconitate 



413 



2.4 

 9-25 

 54.2 

 29.5 

 10.2 

 12.3 

 25.8 

 13.1 



6.7 

 44.3 



3.7 

 11.4 



26.3 



10-17 



72.4 



39.4 



42.3 



36.6 



20.1 



45.7 



16.2 



65.8 



17.6 



45.0 



34.5 



52.5 



42.0 



" The second column shows the 24-hr urinary citrate (mg/kg) in dogs. From Orten 

 and Smith, (1937.) 



The third column shows the urinary concentration of citrate (mg%) in rats. 

 (From Simola and Kosunen, 1938.) 



The fourth and fifth columns show the 24-hr urinary citrate (mg) in rats. (From 

 Krusius, 1940.) 



* Dose in miUimoles per kilogram. 



buted to alkalosis. Crawford (1963) confirmed that the injection of 10 mil- 

 limoles/kg of malonate in rats causes a marked rise in urinary citrate 

 (1.7 -> 47 /^moles/kg/hr), but found that succinate, malate, and sodium 

 bicarbonate also have this effect. Serum citrate simultaneously rises very 

 moderately. It was concluded that all the effects are due to an alkalosis 

 induced by the administration of sodium. However, this cannot account for 

 all of the actions of malonate, nor could it be responsible for the citrate ac- 

 cumulation in cell suspensions and isolated preparations. 



Another possibility is that the citrate arises from the substances that 

 are administered. This was favored by Orten and Smith (1937), but it was 



