6o 



F. EDMUND HUNTER, JR. 



tested. Figure ii illustrates that single or multiple additions of catalase 

 did not significantly alter the effect of ascorbate. Likewise, single or 

 multiple additions of HoOo as such, or generation of H2O2 by the glucose 



0.5 



20 



30 40 50 



MINUTES 



60 



70 80 



Fig. 9. Demonstration that ascorbate-induced lysis of mitochondria occurs 

 after depletion of endogenous substrates (ascorbate added after the mitochon- 

 dria were at 24° for 33 min.) and after phosphate-induced swelling has occurred 

 (ascorbate added at 33 min.). 



5mM PO4+ 0.5mMyg-0H-B 



NHIBITORS 

 , '^ AT 32' 



ASCORBATE + 

 ImM EDTA 

 or AaU ANTIMYCIN A 

 or ImM PYRUVATE 

 "or ZmMNaCNn, 



0.3mM ASCORBATE 

 AT 37' 





\\*n\, control 



\^ v\ ASCORBATE + 

 mM AZIDE 

 or 4mM 



AMYTAL 



ASCORBATE + O.ImM 

 DNP 



40 



50 60 70 

 MINUTES 



80 



90 



Fig. 10. Effect of various inhibitors on ascorbate-induced lysis of mito- 

 chondria after phosphate + ^-hydroxybutyrate-induced swelling has already 

 occurred. 



oxidase system, did not produce an ascorbate-like effect. High concen- 

 trations of glucose oxidase tend to inhibit ascorbate lysis. This is probably 

 due to destruction of ascorbate and to a non-specific protein effect (metal 

 binding }). All evidence on a role for H.2O2 is at present negative. 



