Early receptor potentials of rods and cones in rodents.

摘要: The second phase (negative peak) of the early receptor potential cones has been studied in all-cone eyes Mexican and antelope ground squirrels (Citellus mexicanus Citellus leucurus) compared with responses from rod-dominant rat flying squirrel (Glaucomys volans). obtained tended to be smaller amplitude, have higher thresholds, considerably more resistant light adaptation than eyes. wave forms time courses two types were similar, although cone less sensitive temperature variations its constants shorter those rod potential. spectral sensitivity closely follows absorption spectrum a Dartnall nomogram pigment having maximum at 540 mμ. Moreover, as case rat, amplitude response appears linearly related amount bleached flash. Thus, both all-rod systems arise photoexcitation respective visual linked initial photochemical events. similarity form, course, stimulus-response curves suggests that is produced by similar mechanisms systems.