Identification of 14-hydroxy-4,14-retro-retinol as an in vivo metabolite of vitamin A

Retinol (vitamin A alcohol) undergoes extensive metabolism in vertebrates. We report here (i) the identification of a yet undescribed in vivo metabolite of retinol as 14-hydroxy-4,14-retro-retinol in pregnant mice, rats and rabbits following dosing with vitamin A, and (ii) the preferential accumulation of 14-hydroxy-4,14-retro-retinol in maternal and embryonic tissues, rather than in material plasma.