Light response differences in the superior colliculus of albino and pigmented rats.
Multi-unit visual responses to light intensities ranging from -6.46 to 0.81 logcd/m2 were recorded from the surface of the superior colliculus of dark-adapted normal pigmented and normal albino rats. Light sensitivity was significantly higher in albinos. The response onset latency was inversely proportional to the stimulus intensity. The progression of the stimulus intensity versus response onset latency curve showed a considerable difference between pigmented and albino rats. At low light levels, longer response onset latencies were recorded in pigmented rats than in albinos. This can be attributed to the transmission of rod-driven responses. The differences observed in the light response characteristics of albino rats may be indicative of their visual abnormalities.
Thomas
Biju B
BB
Department of Ophthalmology, Doheny Retina Institute, Doheny Eye Institute, Keck School of Medicine, University of Southern California, DVRC 402, 1355 San Pablo St., Los Angeles, CA 90033, USA.
Aramant
Robert B
RB
Sadda
Srinivas R
SR
Seiler
Magdalene J
MJ
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D015350:Contrast Sensitivity / Q000502:physiology*; D005260:Female; D008297:Male; D008543:Melanins / Q000172:deficiency; D009474:Neurons / Q000502:physiology; D010775:Photic Stimulation; D010857:Pigment Epithelium of Eye / Q000503:physiopathology; D051381:Rats; D011912:Rats, Inbred ACI; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000502:physiology; D012160:Retina / Q000002:abnormalities / Q000502:physiology* / Q000503:physiopathology; D012880:Skin Pigmentation / Q000502:physiology*; D013045:Species Specificity; D013477:Superior Colliculi / Q000502:physiology* / Q000503:physiopathology; D014795:Visual Pathways / Q000002:abnormalities / Q000502:physiology* / Q000503:physiopathology
D008543:Melanins