Excitatory amino acids and cerebrovascular tone.
Levels of excitatory amino acids in the brain extracellular fluid compartment rise during pathological conditions in the brain such as ischaemia, anoxia and epilepsy. One such amino acid, glutamate, is present in sensory nerve fibres innervating, for example, cerebral vessels. Enhanced levels of circulating glutamate and aspartate are found in migraine sufferers. The present study examined whether excitatory amino acids, in concentrations found in the brain extracellular fluid compartment during pathological conditions, exert a direct effect on cerebrovascular tone. As tested in flow-regulating pial arteries from rat, cat and man, no such constrictive or dilatory effect was obtained.
Hardebo
J E
JE
Department of Medical Cell Research, University of Lund, Sweden.
Wieloch
T
T
Kåhrström
J
J
D000328:Adult; D000368:Aged; D000600:Amino Acids, Dicarboxylic / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000378:metabolism*; D001932:Brain Neoplasms / Q000378:metabolism; D002415:Cats; D002536:Cerebral Arteries / Q000187:drug effects*; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D005110:Extracellular Space / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D011921:Rats, Inbred WKY; D017981:Receptors, Neurotransmitter / Q000187:drug effects*
D000600:Amino Acids, Dicarboxylic; D017981:Receptors, Neurotransmitter