Effects of Red Ginseng Extract on Visual Sensitivity and ERG b-wave of Bullfrog's Eye

Abstract

The purpose of the present study was to investigate the effect of red ginseng (Panax ginseng) extracts on the visual process in bullfrog's eye. The results obtained indicated that both dark-adapted and light-adapted ERG b-wave peak amplitude was increased with red ginseng treatment. Furthermore, the ERG sensitivity was elevated by 1.4 log units of light intensity. It was found that red ginseng acts as a retinal neural antagonist but not as a GABA receptor antagonist. Red ginseng improved the alcohol dehydrogenase activity and speeded up the delivery of 11 cis-retinal from retinal pigment epithelium (RPE) to the outer disc of the photoreceptors which resulted in decreased regeneration time of rhodopsin. In the spectral scan, red ginseng treatment brings an increment in absorbance over the whole spectral range (300–800 nm) with maximum difference at around 500 nm. It is concluded that red ginseng may be used to improve visual process, and can potentially be used to treat certain ophthalmic diseases.

Key words

red ginseng - Panax ginseng (Araliaceae) - electroretinogram (ERG) - bullfrog - retina - rhodopsin

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