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Analysis of the macular pigment by HPLC: retinal distribution and age study.

High performance liquid chromatography (HPCL) has been employed to study the distribution throughout the human retina of zeaxanthin and lutein, the two major components of the macular pigment. Differences between individuals have also been studied with a view to uncovering possible age-related effects. Both pigments were detected in prenatal eyes (approximately 20 weeks gestation) but did not form a visible yellow spot. Generally they were not easily discernible until about 6 months after birth. For 87 donors between the ages of 3 and 95, no dependence on age was observed in the quantity of either pigment. For approximately 90% of these, zeaxanthin was dominant. For the remaining 10%, as well as for the seven youngest donors, all below the age of 2, and in prenatal eyes, lutein was the major pigment. In individual retinas, the lutein:zeaxanthin ratio increased from an average of approximately 1:2.4 in the central 0-0.25 mm to over 2:1 in the periphery (8.7-12.2 mm). The variation in this ratio with eccentricity was linearly correlated with the corresponding rod:cone ratio. A selective mechanism of uptake, which results in cones and rods preferentially acquiring zeaxanthin and lutein, respectively, could explain this correlation.