Properties of N-acetylhistamine deacetylase in mammalian brain.
Properties of N-acetylhistamine deacetylase in rat brain were studied, utilizing a sensitive coupled radioenzymatic assay. The Km for N-acetylhistamine for this deacetylase was 660 microM and its Vmax was 330 pmol/h/mg protein. N-Acetylhistamine deacetylase activity increased 80% in the presence of 1 mM Mn2+. The Km of Mn2+ was 40 microM. The enzyme is primarily a soluble enzyme with a relatively uniform regional distribution, unlike the distribution for histamine and histidine decarboxylase. Neonatal activity of this enzyme in rat brain is higher than in adult brain. alpha-Fluoromethylhistidine does not affect the activity of N-acetylhistamine, indicating that deacetylation probably does not play a regulatory role in the synthesis of brain histamine.
D000107:Acetylation; D000375:Aging; D000581:Amidohydrolases / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000201:enzymology*; D002417:Cattle; D006224:Cricetinae; D006168:Guinea Pigs; D006632:Histamine / Q000031:analogs & derivatives / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008297:Male; D008345:Manganese / Q000494:pharmacology; D008647:Mesocricetus; D051379:Mice; D008807:Mice, Inbred BALB C; D011817:Rabbits; D051381:Rats; D011919:Rats, Inbred Strains; D013045:Species Specificity; D013552:Swine; D013816:Thermodynamics; D014018:Tissue Distribution
D008345:Manganese; C021606:N-acetylhistamine; D006632:Histamine; D000581:Amidohydrolases; C018724:N-acetylhistamine amidohydrolase