Phorbol Ester Administration Transiently Increases Aromatic l-Amino Acid Decarboxylase Activity of the Mouse Striatum and Midbrain
Version of Record online: 23 NOV 2002
Journal of Neurochemistry
Volume 63, Issue 2, pages 694–697, August 1994
How to Cite
Young, E. A., Neff, N. H. and Hadjiconstantinou, M. (1994), Phorbol Ester Administration Transiently Increases Aromatic l-Amino Acid Decarboxylase Activity of the Mouse Striatum and Midbrain. Journal of Neurochemistry, 63: 694–697. doi: 10.1046/j.1471-4159.1994.63020694.x
- Issue online: 23 NOV 2002
- Version of Record online: 23 NOV 2002
- Received November 5, 1993; revised manuscript received December 9, 1993; accepted December 31, 1993.
- Aromatic l-amino acid decarboxylase;
- Phorbol ester;
- Protein kinase C;
- Protein phosphatase;
Abstract: Aromatic l-amino acid decarboxylase (AAAD) is required for the synthesis of catecholamines, serotonin, and the trace amines. We found that the protein kinase C activator phorbol 12-myristate 13-acetate administered intracerebroventricularly transiently increased AAAD activity by 30–50% over control values within ∼30 min in the striatum and midbrain of the mouse. The enzyme increase was manifested as an apparent increase of Vmax with little change of Km for either l-3,4-dihydroxyphenylalanine or pyridoxal phosphate. Chelerythrine, a protein kinase C inhibitor, prevented the phorbol ester-induced increase of AAAD. Moreover, okadaic acid, a serine/threonine-selective protein phosphatase 1 and 2A inhibitor, also increased AAAD activity in the mouse striatum and midbrain. Taken together, these observations suggest that protein kinase C-mediated pathways modulate AAAD activity in vivo.