Passage of vasoactive intestinal peptide across the blood-brain barrier.
We investigated the ability of vasoactive intestinal peptide (VIP) to cross the blood-brain barrier (BBB), the interface between the peripheral circulation and central nervous system (CNS). VIP labeled with 131I (I-VIP) and injected intravenously into mice was taken up by brain as determined by multiple-time regression analysis. Excess unlabeled VIP was unable to impede the entry of I-VIP, indicating that passage is by nonsaturable transmembrane diffusion. High pressure liquid chromatography (HPLC) showed the radioactivity entering the brain to be intact I-VIP. After intracerebroventricular (i.c.v.) injection, I-VIP was sequestered by brain, slowing its efflux from the CNS. In summary, VIP crosses the BBB unidirectionally from blood to brain by transmembrane diffusion.
Dogrukol-Ak
Dilek
D
Department of Analytical Chemistry, Faculty of Pharmacy, Anadolu University, 26470 Eskisehir, Turkey. dak@anadolu.edu.tr
Banks
William A
WA
Tuncel
Nese
N
Tuncel
Muzaffer
M
D000818:Animals; D001812:Blood-Brain Barrier / Q000502:physiology*; D001921:Brain / Q000378:metabolism; D002021:Buffers; D002196:Capillaries / Q000502:physiology; D002851:Chromatography, High Pressure Liquid; D007275:Injections, Intravenous; D007457:Iodine Radioisotopes; D008297:Male; D051379:Mice; D000442:Octanols; D021381:Protein Transport; D014660:Vasoactive Intestinal Peptide / Q000008:administration & dosage / Q000134:cerebrospinal fluid / Q000378:metabolism*
D002021:Buffers; D007457:Iodine Radioisotopes; D000442:Octanols; D014660:Vasoactive Intestinal Peptide