ISSN:
1471-4159
Quelle:
Blackwell Publishing Journal Backfiles 1879-2005
Thema:
Medizin
Notizen:
Abstract— The activity of NADPH-linked aldehyde reductase (EC 1.1.1.2) in various regions of monkey brain was determined in vitro. The highest specific activity of the enzyme was found in areas of the brain stem; including the pons, medulla and midbrain. A greater than 500-fold purification of the monkey brain enzyme was obtained by a combination of ammonium sulphate fractionation and subsequent chromatography on calcium phosphate gel cellulose and DEAE-cellulose. The aldehyde metabolites of the biogenic amines, norepinephrine, serotonin, dopamine and octopamine, were readily reduced by the NADPH-linked aldehyde reductase. The Km values for 3,4-dihydroxyphenylglycolaldehyde, 3,4-dihydroxyphenyl-acetaldehyde, and 5-hydroxyindoleacetaldehyde were 12.0 μm, 6.1 μm and 27 μm, respectively. The maximum velocity (Vmax) for 3,4-dihydroxyphenylglycolaldehyde was, respectively, five-fold or three-fold greater than that determined for 3,4-dihydroxyphenylacetaldehyde or 5-hydroxyindoleacetaldehyde. The highly purified enzyme derived from monkey brain was markedly inhibited by barbiturates, diphenylhydantoin, and chlorpromazine, but not by pyrazole. From data obtained by sucrose density gradient centrifugation and Sephadex chromatography the molecular weight of aldehyde reductase was determined to be about 70,000 daltons.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1111/j.1471-4159.1973.tb07525.x
