Brain dopamine receptor levels elevated in canine narcolepsy.
Concentrations of dopamine D2 receptors in discrete brain areas differed significantly between dogs with the genetically transmitted form of narcolepsy, and age- and breed-matched controls. D2 receptors were assayed and quantified with Scatchard analysis using [3H]spiperone. Receptor densities in the nucleus accumbens, rostral caudate, and amygdala were consistently higher in narcoleptic animals. In amygdala, dopamine receptor abnormalities were associated with elevated dopamine and 3,4-dihydroxyphenylacetic acid concentrations, but no change in 3-methoxytyramine or homovanillic acid concentrations. These data indicate mesolimbic system involvement in canine narcolepsy and point to impaired dopamine release as a possible etiologic factor.
D015102:3,4-Dihydroxyphenylacetic Acid / Q000032:analysis; D000679:Amygdala / Q000032:analysis; D000818:Animals; D001923:Brain Chemistry; D002421:Caudate Nucleus / Q000032:analysis; D004285:Dogs; D004298:Dopamine / Q000031:analogs & derivatives / Q000032:analysis; D006719:Homovanillic Acid / Q000032:analysis; D009290:Narcolepsy / Q000378:metabolism*; D009714:Nucleus Accumbens / Q000032:analysis; D011954:Receptors, Dopamine / Q000032:analysis*
D011954:Receptors, Dopamine; D015102:3,4-Dihydroxyphenylacetic Acid; C001746:3-methoxytyramine; D004298:Dopamine; D006719:Homovanillic Acid