Properties of guanylate cyclase in adult rat liver and several Morris hepatomas.
Guanylate cyclase (GTP pyrophyosphate-lyase (cyclizing), EC 4.6.1.2) activity was examined in preparations from normal rat liver and a series of Morris hepatomas. Homogenate gyanylate cyclase activites were 3.2, 1.6 and 1.2 nmol cyclic GMP formed per min/g tissue ihe non-substrate analogs of IMP were weak inhibitors of this enzyme, GMP and four of its analogs had Ki values ranging from 30 to 80 muM. The GMP analogs (8-azaGMP, 7-deaza-8-azaGMP, 2'-dGMP and beta-D-arabinosylGMP) and GMP were competitive inhibitors with respect to GTP.
D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000201:enzymology*; D004789:Enzyme Activation; D006162:Guanylate Cyclase / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008113:Liver Neoplasms / Q000201:enzymology*; D008274:Magnesium / Q000494:pharmacology; D008345:Manganese / Q000494:pharmacology; D009374:Neoplasms, Experimental / Q000201:enzymology; D011092:Polyethylene Glycols / Q000494:pharmacology; D051381:Rats; D013347:Subcellular Fractions / Q000201:enzymology; D013997:Time Factors
D011092:Polyethylene Glycols; D008345:Manganese; D006162:Guanylate Cyclase; D008274:Magnesium