Pharmacological modification of eye growth in normally reared and visually deprived chicks.
Regular injections of the gliotoxins D-alpha-aminoadipic acid and L-alpha-aminoadipic acid were made into the vitreous chamber of the eyes of newly-hatched chicks reared either in a normal visual environment or under conditions of monocular occlusion. Striking differences in the growth rates of the eyes from the different groups were observed. Injection of D-alpha-aminoadipic acid, which causes the Müller glial cells to swell and diminishes the retinal OFF-response, resulted in a marked increase in the rate of axial growth of the eye compared with normal eyes. However, injection of D-alpha-aminoadipic acid into occluded eyes caused a lesser growth rate than was observed in occluded control eyes. By contrast, injection of L-alpha-aminoadipic acid, which also causes severe glial swelling and abolishes the retinal ON-response, caused reduced eye growth in non-occluded eyes. However, injection of L-alpha-aminoadipic acid into occluded eyes caused eye growth in excess of that recorded in the occluded controls. We concluded that the different growth rates observed is more likely a result of the disruption of the neural ON and OFF mechanisms than of the indisposition of the Müller cells.
Visual Science Unit, School of Optometry, University of New South Wales, Kensington, Australia.
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D015074:2-Aminoadipic Acid / Q000494:pharmacology*; D000818:Animals; D001699:Biometry; D002645:Chickens; D005123:Eye / Q000000981:diagnostic imaging / Q000187:drug effects / Q000254:growth & development*; D005260:Female; D005912:Gliotoxin / Q000494:pharmacology*; D006128:Growth / Q000187:drug effects; D008297:Male; D012160:Retina / Q000187:drug effects; D012165:Retinal Ganglion Cells / Q000187:drug effects; D012683:Sensory Deprivation; D013237:Stereoisomerism; D014463:Ultrasonography; D015349:Vision, Monocular / Q000187:drug effects; D014822:Vitreous Body / Q000187:drug effects
D015074:2-Aminoadipic Acid; D005912:Gliotoxin