Study of experimental cataract produced by sugar alcohols in the organ-cultured mammalian ocular lens

Freshly isolated rabbit lenses were cultured in isosmolar TC-199 medium or hyperosmolar medium containing 180 mM sorbitol or mannitol. These experiments were performed to investigate the probable effects of hyperosmolar media on lens clarity and the ability of lens fiber cells to synthesize membrane intrinsic protein, MP-26. The data from these experiments show that incubation in hyperosmolar medium causes depressed MP-26 synthesis, whereas the presence of sugar alcohols in the culture medium induced anterior and posterior subcapsular opacities. The cation levels of lenses incubated in iso- and hyperosmolar medium were also measured. Data from these experiments revealed that although the experimental lenses display prominent opacities, their cation levels are generally similar to those of control lenses. It is proposed that the observed lens opacities are due to the presence of sugar alcohols in the culture medium and not to hyperosmolar shock.