D-1 type of dopamine autoreceptors are not involved in the regulation of dopamine synthesis in the striatum.
To clarify if dopamine (DA) synthesis is regulated by D-1 DA receptors located on dopaminergic nerve terminals in the striatum, we investigated effects of D-1 DA receptor agonist and antagonist on striatal 3,4-dihydroxyphenylalanine (DOPA) accumulation induced by gamma-butyrolactone in mice treated with an amino acid decarboxylase inhibitor. SKF 38393, a D-1 agonist, did not affect DOPA accumulation, whereas apomorphine that stimulates both D-1 and D-2 receptors inhibited the accumulation. SCH 23390, a D-1 antagonist, did not antagonize apomorphine-induced inhibition of DOPA accumulation, while YM-09151-2, a D-2 antagonist, reversed it. These results suggest that D-1 type of DA autoreceptors is not involved in the inhibition of in vivo DA synthesis.
D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D015107:4-Butyrolactone / Q000494:pharmacology; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D001552:Benzazepines / Q000494:pharmacology; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism*; D004298:Dopamine / Q000096:biosynthesis*; D008297:Male; D051379:Mice; D011954:Receptors, Dopamine / Q000187:drug effects / Q000502:physiology*
D001552:Benzazepines; D011954:Receptors, Dopamine; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D001058:Apomorphine; D015107:4-Butyrolactone; D004298:Dopamine