GOLCI MliMBRANES 



119 



Fig. 4. I)cnsit\ ijradicnt fraction- 

 ation of rat epididymis (for ex- 

 planation, see legend for fig. 3). 

 In this instance, the homogenatc 

 was subjected to a prior low speed 

 centrifugation to remove the sperm, 

 nuclei and whole cells, and the re- 

 sultant extract (E) was layered in 

 the position indicated. Centrifuga- 

 tion was for 1 hour at 35,600 rpm. 



246810 2468 10 



RELATIVE CONCENTRATION 



employed is illustrated in figure 5. The tissue was homogenized in three volumes 

 of 1.45 M (50/t) sucrose containing 0.34 m sodium chloride, the final density of 

 the homogenate being about 1.15 grams per centimeter'. Sperm and neutral fat 

 were removed by a preliminary low-speed centrifugation, and the resultant extract 

 (E) placed at the bottom of a centrifuge tube. The usual density gradient was 

 then formed above the extract and centrifugation carried out as before. It was 



>0G 



>UG 



S' 



Sed. 



DPNH- 

 TOTAL RNA CYTOC LIPID ACID ALK. 



N RED P P'ASE P'ASE 



% 



0.1 



I.I 



0.9 



I , [ . I 



I.I.I 



I.I.I II 



24 246 246 2468 10 



RELATIVE CONCENTRATION 



Fig. 5. Density gradient fracti(jnation of rat eiiididymis (for explanation, see legends for 

 figs. 3 and 4). The initial position of the extract, E, was at the bottom of the centrifuge tube. 

 Centrifugation was for i hour at 35,600 rpm. 



