GLUCOSE AND OXYGEN UTILIZATION IN SYMPATHETIC GANGLIA 



85 



TABLE I 



Metabolic effects of anesthetics in concentrations causing 



50% reduction in postganglionic response 



Agent Causing 50% Block 



Chloretone. . . 

 Chloroform . . 



Ether 



Pentobarbital . 

 Urethane .... 



Ethanol 



Hexanol 



Octanol 



Rate of Uptake as Per Cent of Control 



A 



Oxygen 

 Rabbit 



97 

 100 

 100 

 100 



94 

 100 



100 



B 



Oxygen 



Rat 



60 



103 

 68 



86 



C 



Glucose 



Rat 



160 



164 



92 



A. From Larrabee, Ramos and Biilbring (1952). 



B. and C. From Edwards and Larrabee (1955). 



on brain tissue can be avoided. Advantages are that observations can be made 

 in various controlled states of activity, the response to stimulation can be 

 measured accurately by recording from the preganglionic and postganglionic 

 nerves, and the effects of anesthetics on metabolic exchange and nervous func- 

 tion can be observed simultaneously or at least under similar conditions. 



Anesthetics on Metabolism of Ganglia at Rest 



Our first metabolic experiments in connection with anesthetics were con- 

 cerned with the resting rate of oxygen uptake by superior cervical ganglia 

 excised from rabbits. Most, if not all, of the anesthetics employed depressed 

 the resting rate of oxygen consumption when present in sufficient concentra- 

 tions. This is in agreement with the results of many investigators on brain 

 (Quastel, 1952). More significant, however, was the finding that resting oxygen 

 uptake was not significantly disturbed at the minimal concentrations required 

 for impairment of ganglionic transmission (Table I, Column A). 



Results different from those on rabbits were obtained on ganglia excised from 

 rats (Edwards and Larrabee, 1955). Here it was found that oxygen uptake was 

 definitely slowed by at least three agents in concentrations causing 50% block 

 of transmission (Table I, Column B). Moreover there was additional evidence 

 of a metabolic disturbance, since the rate of glucose uptake was found to be 

 considerably increased by certain agents, as shown in Column C of Table I. 

 This is in agreement with results of several studies on brain (Greig, 1947; 

 Mcllwain, 1953 ; Rosenberg, Buchel, Etting and Levy, 1950; Webb and Elliott, 

 1951). 



