Effect of vitamin A on glycoconjugate: synthesis in the trabecular meshwork. A preliminary report

We studied the effect of vitamin A on glycoconjugate synthesis in trabecular meshwork (TM) cells in vivo. The aqueous flow system of two cats and one monkey was exposed in vivo to retinoic acid dissolved in dimethyl sulfoxide (DMSO). One hour prior to enucleation, [3H]glucosamine was injected into all eyes. The tissue was subsequently processed for autoradiography. The density of grains (grains micron-2) in the vitamin A-treated eyes of Cats I and II was 77% and 30% less, respectively, than the density of grains in the control eyes. In the monkey the grain density was 56% less in the experimental eye compared with the control eye. These data suggest that exogenous vitamin A suppresses glycoconjugate synthesis in TM cells in vivo.