Sugar cataracts in Mongolian gerbil (Meriones unguiculatus).

Mongolian gerbils (Meriones unguiculatus) given a 50% galactose diet developed cataracts similar to those produced in rats maintained on the same diet. This report describes the various stages through which the cataracts progressed. The first sign of a cataract appeared 24 hr after feeding gerbils on the high galactose diet. The pace of cataract maturation was observed to be about twice of that in rats, although the blood galactose levels were similar in the two species. Aldose reductase activity in the gerbil lens was also about twice of that in the rat lens. In conformity with this, dulcitol accumulated to a higher level in gerbil lens during the early phase of cataractogenesis. The data are, therefore, in accordance with the concept that excessive accumulation of polyol in the lens initiates cataract development. The gerbil thus appears to be another suitable model for the study of sugar cataracts.