title: Preservation of dopamine release in the denervated striatum.
abstract: Dopamine metabolism and release were determined in the striata of rats sustaining varying damage to the nigrostriatal dopamine (DA) projection. DA metabolism, inferred from concentrations of dihydroxy-phenylacetic acid (DOPAC) or homovanillic acid (HVA), decreased with DA denervation of more than 20%. Dopamine release, inferred from the concentration of 3-methoxytyramine (3-MT), did not decrease unless the denervation was at least 80%. The amount of 3-MT per surviving neuron exceeded that for DOPAC over most of the denervation range. Thus, striatal DA release is preserved at normal levels with the survival of only 20% of the striatal DA innervation. Decreases in DA release, rather than decreases in DA metabolism or the density of dopamine innervation, coincide with the appearance of behavioral impairments.
authors.affiliation: Pharmaceuticals Division, Ciba-Geigy Corporation, Summit, NJ 07901.
authors.forename: C A
authors.initials: CA
authors.lastname: Altar
authors.forename: M R
authors.initials: MR
authors.lastname: Marien
mesh_terms: D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D004298:Dopamine / Q000031:analogs & derivatives / Q000378:metabolism* / Q000502:physiology; D006719:Homovanillic Acid / Q000378:metabolism; D006892:Hydroxydopamines; D008297:Male; D016627:Oxidopamine; D051381:Rats; D011919:Rats, Inbred Strains; D013378:Substantia Nigra / Q000502:physiology*
chemical_list: D006892:Hydroxydopamines; D015102:3,4-Dihydroxyphenylacetic Acid; D016627:Oxidopamine; C001746:3-methoxytyramine; D004298:Dopamine; D006719:Homovanillic Acid