Inhibition of matrix metalloproteinase activity in the chick sclera and its effect on myopia development

Abstract

PURPOSE. To investigate the contribution of matrix degradation in the two-layer avian sclera to the development of myopia. METHODS. Tissue inhibitor of metalloproteinase-2 (TIMP-2) was used to inhibit chick scleral collagen degradation with 3Hproline, a marker for this effect. Ex vivo scleral culture experiments confirmed TIMP-2 doses for in vivo experimentation. Ocular growth and refractive response to exogenous TIMP-2 (11.25, 2.25, and 0.45 picomoles, plus vehicle only) were monitored in 7-day-old chicks during the induction of myopia over 4 days with a translucent occluder. Collagen degradation was assessed, in whole sclera and in separated scleral layers by using the same paradigm (11.25..