[Comparative study of the action of O-phenanthroline metal complexes and a number of other compounds on the activity of brain arginase isoforms].
Two isoforms of arginase were isolated from rat brain tissue: isoform I-adsorbed on CM-Sephadex and isoform II-unadsorbed on the sorbent. In samples with arginine as a substrate Km values for isoforms I and II constituted 1.7 X 10(-3) M and 3.8 X 10(-3) M, respectively. EDTA and o-phenanthroline inhibited these both brain arginase isoforms. As shown in experiments with o-phenanthroline metal complex affecting the brain arginase activity some copper complexes were able to inhibit most effectively the activity of the isoform II. Activity of both these isoforms was inhibited also by dithiothreitol, proline and acetaldehyde. Complexes of o-phenanthroline with Co2+ and Fe2+ inhibited only slightly the activity of the isoform II and did not affect the isoform I. These data showed that brain arginase isoforms were markedly distinct in their properties from the ureotelic liver tissue arginase.
D000818:Animals; D001119:Arginase / Q000037:antagonists & inhibitors*; D001921:Brain / Q000187:drug effects* / Q000201:enzymology; D007527:Isoenzymes / Q000037:antagonists & inhibitors*; D008099:Liver / Q000187:drug effects / Q000201:enzymology; D009942:Organometallic Compounds / Q000494:pharmacology*; D010618:Phenanthrolines / Q000494:pharmacology*; D051381:Rats; D014508:Urea / Q000378:metabolism
D007527:Isoenzymes; D009942:Organometallic Compounds; D010618:Phenanthrolines; D014508:Urea; D001119:Arginase; C025205:1,10-phenanthroline
Sravnitel'noe izuchenie deĭstviia O-fenantrolinovykh metallokompleksov i riada drugikh soedineniĭ na aktivnost' izoform arginazy mozga.