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.
Crewther
D P
DP
Visual Science Unit, School of Optometry, University of New South Wales, Kensington, Australia.
Crewther
S G
SG
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