title: Evaluation of retinal susceptibility to light damage in pigmented rats supplemented with beta-carotene.
abstract: The present study evaluated the influence of beta-carotene supplementation on the susceptibility of the retina to light damage. Long-Evans pigmented rats were supplemented with beta-carotene by either dietary or intraperitoneal administration, and beta-carotene levels in plasma, liver and retina were determined by high performance liquid chromatography. Other animals from each group were exposed to ultraviolet-A light at a dose of 8.1 J/cm2 in their right eye only, and photoreceptor cell losses determined by light microscopic morphometry. In supplemented animals, beta-carotene levels increased markedly in the liver, and were elevated from non-detectable to detectable in the plasma and retina, relative to nonsupplemented controls. In each tissue, beta-carotene levels were found to be higher in animals receiving intraperitoneal supplementation as compared to dietary. Beta-carotene supplementation by either route did not protect the retina against photoreceptor cell loss measured at two weeks following UVA exposure. Preliminary observations indicated that beta-carotene supplementation decreased the incidence of light-induced retinal pigment epithelium destruction.
authors.affiliation: Cullen Eye Institute, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: L M
authors.initials: LM
authors.lastname: Rapp
authors.forename: P L
authors.initials: PL
authors.lastname: Fisher
authors.forename: D W
authors.initials: DW
authors.lastname: Suh
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D000975:Antioxidants / Q000494:pharmacology*; D004198:Disease Susceptibility; D007274:Injections, Intraperitoneal; D008854:Microscopy, Electron; D010857:Pigment Epithelium of Eye / Q000528:radiation effects / Q000648:ultrastructure; D010858:Pigmentation; D051381:Rats; D011919:Rats, Inbred Strains; D012160:Retina / Q000187:drug effects* / Q000528:radiation effects* / Q000648:ultrastructure; D014466:Ultraviolet Rays; D019207:beta Carotene / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D019207:beta Carotene