Retinoic acid signals the direction of ocular elongation in the guinea pig eye.
A growing eye becomes myopic after form deprivation (FD) or compensates for the power and sign of imposed spectacle lenses. A possible mediator of the underlying growth changes is all-trans retinoic acid (RA). Eye elongation and refractive error (RE) was manipulated by raising guinea pigs with FD, or a spectacle lens worn on one eye. We found retinal-RA increased in myopic eyes with accelerated elongation and was lower in eyes with inhibited elongation. RA levels in the choroid/sclera combined mirrored these directional changes. Feeding RA (25 mg/kg) repeatedly to guinea pigs, also resulted in rapid eye elongation (up to 5 times normal), and yet the RE was not effected. In conclusion, RA may act as a signal for the direction of ocular growth.
McFadden
Sally A
SA
School of Behavioural Sciences, Faculty of Science and IT, The University of Newcastle, NSW 2308, Newcastle, Australia. sally.mcfadden@newcastle.edu.au
Howlett
Marc H C
MH
Mertz
James R
JR
D000284:Administration, Oral; D000818:Animals; D005123:Eye / Q000254:growth & development* / Q000378:metabolism / Q000473:pathology; D006168:Guinea Pigs; D023421:Models, Animal; D009216:Myopia / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D012030:Refractive Errors; D014212:Tretinoin / Q000008:administration & dosage* / Q000032:analysis / Q000378:metabolism; D014785:Vision, Ocular / Q000502:physiology
D014212:Tretinoin