Differential expression of autoreceptors in the ascending dopamine systems of the human brain.
The tone and regulation of the brain dopaminergic projections are, in part, determined by the presence or absence of dopamine (DA) autoreceptors: rate of DA synthesis and turnover, as well as both pattern and rate of neuronal firing, are modulated by the expression and activity of these autoreceptors. The expression of dopaminergic receptors in the midbrain DA cell groups, presumably reflecting DA autoreceptors, was determined in the brains of the rat, Old World monkey, and human. In the rat, both the substantia nigra (A9) and the ventral tegmental area (A10) appear to express DA autoreceptors. In the monkey and human, however, only the projections arising from the substantia nigra express these receptors; the limbic projections originating in the ventral tegmental area lack this substrate for DA autoregulation. These results indicate that in the human, the nigrostriatal and mesocorticolimbic dopamine systems may be differentially autoregulated.
Meador-Woodruff
J H
JH
Mental Health Research Institute, University of Michigan, Ann Arbor 48109.
Damask
S P
SP
Watson
S J
SJ
D000818:Animals; D001345:Autoradiography; D001921:Brain / Q000166:cytology / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*; D006706:Homeostasis; D006801:Humans; D017403:In Situ Hybridization; D008253:Macaca mulatta; D008254:Macaca nemestrina; D008297:Male; D008636:Mesencephalon / Q000378:metabolism; D009928:Organ Specificity; D012333:RNA, Messenger / Q000032:analysis* / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D011954:Receptors, Dopamine / Q000096:biosynthesis*; D017448:Receptors, Dopamine D2 / Q000096:biosynthesis*; D050637:Receptors, Dopamine D3; D013045:Species Specificity; D013378:Substantia Nigra / Q000378:metabolism; D013462:Sulfur Radioisotopes; D014446:Tyrosine 3-Monooxygenase / Q000096:biosynthesis
C493593:DRD3 protein, human; C493595:Drd3 protein, rat; D012333:RNA, Messenger; D011954:Receptors, Dopamine; D017448:Receptors, Dopamine D2; D050637:Receptors, Dopamine D3; D013462:Sulfur Radioisotopes; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine