FRANK H. JOHNSON 



279 



1,000 2,000 3,000 4,000 5,000 6,000 7,000 



Pressure (psi) 



Fig. 9. Luminescence intensity of P. phosplioreum as a function of hydrostatic 

 pressure at 17.5° C, in the presence of various concentrations of alcohol in 

 the phosphate-buffered sodium chloride solution, pH 7, of the suspending 

 medium. ( From Johnson, Eyring, and Polissar, 1954, courtesy of John Wiley 

 & Sons; data of Johnson et ah, 1945. ) 



narcosis of these aquatic animals, respectively, by various drugs, i.e., 

 the effects of different dmgs on both luminescence and narcosis ex- 

 hibit varying degrees of sensitivity to pressure that are at least quali- 

 tatively the same in the two phenomena. 



Multiple Equilibria in Reversible Effects of Narcotics 



At a given temperature and pressure, the relation between drug 

 concentration and amount of inhibition of luminescence by alcohol 

 or urethan often conforms rather closely to the relationship which 

 would be expected if the drug entered into a single equilibrium 

 combination with the enzyme affected. The relationship should be 



