LACTATE DEHYDROGENASE IN THE RETINA OF THE GUPPY 



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The first appearance of the E-bands on starch gel is observed in an embryo 

 )f 20 days (stage 7). They show, already, adult distribution of intensity; they are, 

 îowever, much weaker (fig. 13). Histological staining of the eye reveals that 



Fie. 13. 



Lactate dehydrogenase isozymes of Lebistes eye at stage 7 

 (20th embryonic day) showing présence of E-bands. 



Fig. 14. 



Retina of stage 7, with differentiated photoreceptors and retinomotor response (azan stain). 



Fig. 15. 



Retina of stage 6, Photoreceptors présent, but not yet differentiated (azan stain). 



Fig. 16. 



Lactate dehydrogenase isozymes of Lebistes eye at stage 6 (15th embryonic day). 



No E-bands présent. 



ail three types of cônes and the rods are differentiated at this stage (fig. 14). 

 As a comparison, stage 6 (15th day) is shown; at this stage the photoreceptors 

 are présent but not yet differentiated, and the E-bands are not yet resolved 

 (figs. 15 and 16). LDH staining of the kryostat sections of stage 7 shows a 



