Restricted transport of vitamin D and A derivatives through the rat blood-brain barrier.
The present studies measure the transport of retinol, retinoic acid, 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3], and 25-hydroxyvitamin D3 [25-(OH)D3] through the rat brain capillary endothelial wall, i.e., the blood-brain barrier (BBB). The vitamin A and D derivatives bind both to albumin and to specific high-affinity binding proteins in plasma. In the presence of physiologic concentrations of plasma proteins, the extraction by brain of all four compounds was 5% or less.
D000818:Animals; D001692:Biological Transport; D001769:Blood; D001812:Blood-Brain Barrier; D001921:Brain / Q000378:metabolism; D002112:Calcifediol / Q000378:metabolism; D002117:Calcitriol / Q000378:metabolism; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D014212:Tretinoin / Q000378:metabolism; D014801:Vitamin A / Q000378:metabolism*; D014807:Vitamin D / Q000378:metabolism*
D014801:Vitamin A; D014807:Vitamin D; D014212:Tretinoin; D002117:Calcitriol; D002112:Calcifediol