l-3,4-Dihydroxyphenylalanine induces ptosis through a GPR143-independent mechanism in mice.
Through its conversion to dopamine by aromatic l-amino acid decarboxylase (AADC), l-3,4-dihydroxyphenylalanine (l-DOPA) replenishes depleted brain dopamine in Parkinson's disease patients. We recently identified GPR143 as a candidate receptor for l-DOPA. In this study, we investigated the behavioral actions of l-DOPA in wild type (wt) and Gpr143-deficient mice. l-DOPA dose-dependently (10-100 mg/kg, i.p.) induced ptosis under treatment with 3-hydroxybenzylhydrazine, a centrally acting AADC inhibitor. This effect was not mimicked by 3-O-methyldopa. l-DOPA-induced ptosis in Gpr143-deficient mice to a similar extent as in wt mice. These results suggest that l-DOPA induces ptosis in a GPR143-independent fashion in mice.
Department of Molecular Pharmacology and Neurobiology, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan.
Suguru
S
Ueda
Department of Molecular Pharmacology and Neurobiology, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan.
Daiki
D
Masukawa
Department of Molecular Pharmacology and Neurobiology, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan.
Motokazu
M
Koga
Department of Molecular Pharmacology and Neurobiology, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan. Electronic address: goshima@yokohama-cu.ac.jp.
Yoshio
Y
Goshima
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001763:Blepharoptosis / Q000139:chemically induced* / Q000378:metabolism; D005136:Eye Proteins / Q000235:genetics / Q000378:metabolism; D007980:Levodopa; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism
D005136:Eye Proteins; C506821:Gpr143 protein, mouse; D008562:Membrane Glycoproteins; D043562:Receptors, G-Protein-Coupled; D007980:Levodopa
GPR143; Ptosis; l-DOPA