Enzymes Controlling the Biosynthesis of Catecholamines
Isotopic studies have confirmed the proposed major pathway for the biogenesis of norepinephrine and epinephrine . The main steps in this pathway are the oxidation of phenylalanine to tyrosine followed by hydroxylation to 3,4-dihydroxyphenylalanine, decarboxylation to dopamine, β-hydroxylation of dopamine to norepinephrine and N-methylation of norepinephrine to epinephrine. In addition, some other minor pathways were postulated (Fig. 1). Although evidence for the main pathway was well established a decade ago, only recently, all the enzymes which control the biosynthesis of catecholamines were isolated and their properties characterized. Based on these studies it is now possible to investigate the activities of these enzymes in tumors such as neuroblastoma and pheochromocytoma, and to determine which of those enzymes is responsible for the overproduction of catecholamines.
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- Blaschko, H.: In M. Harington (Editor): Hypotensive drugs. London: Pergamon Press 956, p. 23.Google Scholar
- Goldstein, M.: To be published.Google Scholar
- Creveling, C. R.: Ph. D. Thesis, Georgetown University, Washington D.C. 1962.Google Scholar
- Lemberger, L.: Fed. Proc. 23, 2758 (1964).Google Scholar
- Green, A. L.: Biochim. biophys. Acta 81, 394 (1964).Google Scholar
- Goldstein, M.: TO be published.Google Scholar
- Cantoni, G.: Phosphorus Metabolism, vol. I p. 641. Ed. by W. D. McElroy and B. Glass. Baltimore: Johns Hopkins Press 1951.Google Scholar
- Kelly, H. M.: Proc. Staff Meet. Mayo Clin. 11, 65 (1936).Google Scholar
- Studnitz, W. VON: Lancet 1961, 215.Google Scholar
- Studnitz, W. VON: This meeting.Google Scholar