Sass J O, Masgrau E, Piletta P A, Nau H, Saurat J H
Institute for Toxicology and Embryopharmacology, Free University Berlin, Germany.
Skin Pharmacol. 1996;9(5):322-6. doi: 10.1159/000211436.
Retinaldehyde (RAL), a natural metabolite of beta-carotene and retinol (ROL), is tolerated by human skin after topical application.
To see if topical application of a large quantity of RAL on human skin is associated with a detectable alteration of constitutive levels of plasma retinoids resulting from metabolism of RAL in the skin.
Plasma retinoids [ROL, all-trans-retinoic acid (all-trans-RA), RAL, retinyl palmitate/oleate, 13-cis-RA and 4-oxo-13-cis-RA] were analyzed by high-pressure liquid chromatography. Determinations were done in 10 healthy male volunteers kept on a vitamin-A-poor diet before, during and after daily topical application of 7 mg of RAL to 40% of the body surface for 14 days.
The introduction of a restricted vitamin A diet before RAL application resulted in a decrease in the plasma levels of ROL, all-trans-RA and retinyl palmitate/oleate. Topical application of RAL did not induce an alteration of the plasma levels of retinoid metabolites. No RAL was detectable in any of the plasma samples.
The skin metabolism of topically applied RAL does not result in detectable alterations of constitutive levels of plasma retinoids in humans.
视黄醛（RAL）是β-胡萝卜素和视黄醇（ROL）的天然代谢产物，局部应用后人体皮肤可耐受。
观察在人体皮肤上大量局部应用RAL是否会因皮肤中RAL的代谢而导致血浆类视黄醇组成水平发生可检测到的改变。
采用高压液相色谱法分析血浆类视黄醇[ROL、全反式视黄酸（全反式RA）、RAL、棕榈酸视黄酯/油酸视黄酯、13-顺式视黄酸和4-氧代-13-顺式视黄酸]。对10名健康男性志愿者进行测定，他们在每日将7mg RAL局部涂抹于40%体表14天之前、期间和之后，保持低维生素A饮食。
在应用RAL之前采用限制维生素A饮食导致血浆中ROL、全反式视黄酸和棕榈酸视黄酯/油酸视黄酯水平降低。局部应用RAL未引起血浆类视黄醇代谢物水平的改变。在任何血浆样本中均未检测到RAL。
局部应用的RAL在人体皮肤中的代谢不会导致血浆类视黄醇组成水平发生可检测到的改变。
