Category: vitamin
Aliases: Vitamin A, Preformed Vitamin A, Retinyl palmitate, Retinyl acetate
Retinol is oxidised to retinal (11-cis-retinal in rhodopsin → vision) and further to retinoic acid, which binds RAR/RXR nuclear receptors and regulates >500 genes controlling epithelial differentiation, immune function, and embryonic development. Stored in liver as retinyl esters; preformed vitamin A accumulates (unlike β-carotene where conversion is regulated).