title: Osmotic opening of the blood-brain barrier to methotrexate in the rat.
abstract: Osmotic opening of the blood-brain barrier in the rat, by intracarotid infusion of 1.6 molal (m) arabinose solution, increases cerebrovascular permeability to 3H-methotrexate by a factor of about seven. PA (product of permeability and capillary surface area) increases from a mean of 3.3 X 10(-5) sec-1 in brains of control rats to as much as 28 X 10(-5) sec-1 at the cerebral hemisphere ipsilateral to carotid infusion. If tracer is introduced into the carotid artery after osmotic treatment, brain uptake is increased by a net factor of 50 (a factor of 70 due to elevation of PA, multiplied by 7 due to infusion by the carotid route) as compared to uptake by normal, untreated brain with infusion into a peripheral vein. Osmotic barrier opening followed by carotid drug administration may be of use in experimental chemotherapy of nervous system disease.
mesh_terms: D000818:Animals; D001089:Arabinose / Q000494:pharmacology; D001812:Blood-Brain Barrier / Q000187:drug effects*; D001921:Brain / Q000378:metabolism*; D008297:Male; D008727:Methotrexate / Q000378:metabolism*; D009995:Osmosis / Q000187:drug effects; D010539:Permeability; D051381:Rats
chemical_list: D001089:Arabinose; D008727:Methotrexate