title: Effect of dietary n-3 deficiency on the electroretinogram in the guinea pig.
abstract: Despite the abundance of n-3 polyunsaturated fatty acids, particularly docosahexaenoic acid (DHA), in the retina of all mammals, their role in vision remains unclear. However, the widely accepted notion that DHA is universally important in the retinal function was questioned in an earlier study (see text) involving guinea pigs, completely depleted of retinal DHA. The purpose of this study was to replicate this mammalian model of such deficiency and to determine any abnormalities in the electroretinogram. Guinea pigs were raised through three generations on 1 of 2 semipurified diets, containing different amounts of n-3 fatty acids, as determined by the supplementary oil which was the sole source of lipid in each diet. The added oils were safflower oil (n-6/n-3 = 72.0) or canola oil (n-6/n-3 = 2.5). Comprehensive electroretinographic assessment was conducted on guinea pigs, aged 6-9 weeks (safflower n = 13, canola n = 12), and retinae were extracted and the phospholipid fatty acid profile analyzed. Phospholipid fatty acid analysis revealed significant DHA deficiency (p < 0.001) in guinea pigs reared on the safflower oil diet (retinal DHA 2.5%) as compared with the canola oil group (retinal DHA 21.0%). Analysis of the electroretinogram showed significant reductions (p < 0.003) in both peak-to-peak and a-waves of safflower oil fed animals.
authors.affiliation: Department of Optometry and Vision Sciences, University of Melbourne, Parkville, Vic., Australia.
authors.forename: H S
authors.initials: HS
authors.lastname: Weisinger
authors.forename: A J
authors.initials: AJ
authors.lastname: Vingrys
authors.forename: A J
authors.initials: AJ
authors.lastname: Sinclair
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004281:Docosahexaenoic Acids / Q000032:analysis; D004596:Electroretinography; D005229:Fatty Acids, Monounsaturated / Q000494:pharmacology; D015525:Fatty Acids, Omega-3 / Q000032:analysis / Q000502:physiology*; D005260:Female; D005527:Food, Fortified; D006168:Guinea Pigs; D008297:Male; D010743:Phospholipids / Q000032:analysis; D000074262:Rapeseed Oil; D012160:Retina / Q000737:chemistry / Q000502:physiology*; D012450:Safflower Oil / Q000494:pharmacology
chemical_list: D005229:Fatty Acids, Monounsaturated; D015525:Fatty Acids, Omega-3; D010743:Phospholipids; D000074262:Rapeseed Oil; D004281:Docosahexaenoic Acids; D012450:Safflower Oil