Gamma-aminobutyric acid (GABAB) receptor-mediated inhibition of tyrosine hydroxylase activity in the striatum of rat.
The effects of GABA and GABA agonists on calcium and depolarization-dependent stimulation of tyrosine hydroxylase activity in striatal slices were studied. gamma-Aminobutyric acid and (-)baclofen inhibited, while muscimol and (+)baclofen did not affect, the stimulation of tyrosine hydroxylase. The inhibitory effect of GABA and (-)baclofen was blocked by the GABAB antagonist, phaclofen but not by the GABAA antagonist, picrotoxin. The data suggest that the activity of tyrosine hydroxylase on dopaminergic nigrostriatal terminals may be modulated by GABA via GABAB receptors.
Departamento de Fisiología, Biofísica y Neurociencias, Instituto Politécnico Nacional de México.
J A
JA
Arias-Montaño
D
D
Martínez-Fong
J
J
Aceves
D000818:Animals; D065105:Aromatic Amino Acid Decarboxylase Inhibitors; D001418:Baclofen / Q000031:analogs & derivatives / Q000494:pharmacology; D002118:Calcium / Q000502:physiology; D003342:Corpus Striatum / Q000187:drug effects / Q000201:enzymology*; D004295:Dihydroxyphenylalanine / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism; D006834:Hydrazines / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D009118:Muscimol / Q000494:pharmacology; D009434:Neural Pathways / Q000187:drug effects / Q000502:physiology; D010852:Picrotoxin / Q000494:pharmacology; D011189:Potassium Chloride / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011963:Receptors, GABA-A / Q000187:drug effects*; D013378:Substantia Nigra / Q000187:drug effects / Q000201:enzymology; D014446:Tyrosine 3-Monooxygenase / Q000037:antagonists & inhibitors*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism / Q000494:pharmacology
D065105:Aromatic Amino Acid Decarboxylase Inhibitors; D001418:Baclofen; D002118:Calcium; D004295:Dihydroxyphenylalanine; D004298:Dopamine; D006834:Hydrazines; D009118:Muscimol; D010852:Picrotoxin; D011189:Potassium Chloride; D011963:Receptors, GABA-A; D014446:Tyrosine 3-Monooxygenase; D005680:gamma-Aminobutyric Acid; C052329:phaclofen; C004297:3-hydroxybenzylhydrazine