ERGOTHIONEINE DISTRIBUTION IN BOVINE AND PORCINE OCULAR-TISSUES

Ergothioneine (ERT), is a low molecular weight, sulfur containing anti oxidant occurring in up to millimolar amounts in mammalian tissues. Us ing an improved HPLC assay, ERT levels have been measured and compared in bovine and porcine eyes and erythrocytes. The rank order of ERT le vels in bovine ocular tissue was lens >retina=cornea >pigmented retina l epithelium (RPE) >aqueous humor (AQ) >vitreous humor (VIT) >sclera. In porcine ocular tissue, the rank order was retina >AQ >VIT >RPE >cor nea >lens >sclera. ERT levels in bovine lens were about 250 x >that in porcine lens. Porcine erythrocyte levels were 5.5 X >bovine levels. S pecies differences were also observed in the retina, VIT and Aa where porcine levels were 2 to 10-fold greater than bovine levels. ERT in bo vine lens and cornea was 35 and 14 times greater than the correspondin g level of reduced glutathione (GSH). Porcine lens had 45 times more G SH than ERT. Values for ERT and GSH in other tissues from both species were of the same order of magnitude. These results are consistent wit h a role for ERT in prevention of oxidative damage to the eye. (C) 199 7 Elsevier Science Inc.