118 



PIERRE H. GONSE 



0.01 



0.1 



-1 



1.2 



0.8 



0.6 



0.4 



0.2 



10 mM azide 



Fig. 11. Respiratory rates with increasing concentrations of azide 

 shown for bull spermatozoa. Cells washed and suspended in RP, pH 7.2. 

 Samples H4720, H4715, H4730. x, no addition, low endogenous respira- 

 tion of washed cells; Q, addition of DNP 0.1 mM; A- addition of lac- 

 tate 20 mM; Q . addition of succinate 20 mM; A, addition of lactate 20 

 mM and DNP 0.1 mM; V, addition of lactate 20 mM and DNP 0.2 mM. 



seems to be a function of the turnover of the preparation as seen 

 more clearly with experiments on titration of respiration as a func- 

 tion of increasing azide concentrations (Fig. 11). These experiments 

 were carried out on bull spermatozoa pretreated so as to be in the 

 various metabolic states defined by Chance and Williams (1956). 

 These are as follows: state 1, very low respiration of starved cells; 



