Abstract
Purpose: :
The study compared the effects of diuretic substances that inhibit retinal pigment epithelium (RPE) cotransport systems on defocus induced refractive error induction in chicks.
Methods: :
57 chicks were fitted with +10D, -10D lenses or wore no lens on the right eye, from day 5 to day 9 after hatching. The right eye was injected with 5µl of 1 mM amiloride, 1 mM bumetanide, or 1 mM furosemide dissolved in DMSO, or DMSO alone. Fellow eyes received the same volume of DMSO. Chicks were reared on a 12 hr light 12 hr dark cycle and had unlimited food and water and were maintained at 31°C. Biometry including retinoscopy and A-scan ultrasonography, which were performed on day 9. Electroretinography was performed on subgroups of chicks (generally n=3).
Results: :
All three diuretics showed an ability to prevent the full compensation to -10D lenses, however the responses to +ve lenses was more varied. Rather than the diuretic forcing an overall reduction of fluid in the eye, such changes were only observed in combination with negative defocus a condition normally associated with retention of water in the eye.
Conclusions: :
All three diuretics showed an ability to prevent the full compensation to -10D lenses, however the responses to +ve lenses was more varied. Rather than the diuretic forcing an overall reduction of fluid in the eye, such changes were only observed in combination with negative defocus a condition normally associated with retention of water in the eye. The results are discussed with respect to the electrophysiological effects of these diuretics on retinal function.
Keywords: myopia • drug toxicity/drug effects