Catabolism of N-acylethanolamine phospholipids by dog brain preparations.
N- Acylphosphatidylethanolamine , incubated with dog brain homogenate or microsomes, was hydrolyzed to phosphatidic acid and N-acylethanolamine by a phosphodiesterase of the phospholipase D type. In the absence of F-, phosphatidic acid was further hydrolyzed to diacylglycerol and Pi while N-acylethanolamine was hydrolyzed by an amidase to fatty acid and ethanolamine. The phosphodiesterase showed an alkaline pH optimum and was also active towards N- acetylphosphatidylethanolamine , N-acyl-lysophosphatidylethanolamine, and glycerophospho (N-acyl)ethanolamine but showed little activity toward phosphatidylethanolamine and phosphatidylcholine. Ca2+ stimulated slightly at low concentrations but inhibited at higher concentrations. Triton X-100 stimulated the hydrolysis of N- acylphosphatidylethanolamine , inhibited that of N-acyl-lysophosphatidylethanolamine and glycerophospho (N-acyl)ethanolamine, and had no effect on phosphatidylethanolamine or phosphatidylcholine hydrolysis. The N-acylethanolamine hydrolase (amidase) was also present in the microsomal fraction and exhibited a pH optimum of 10.0. In addition to hydrolysis by the phosphodiesterase, N- acylphosphatidylethanolamine was also catabolized by microsomal phospholipases A1 and/or A2 to N-acyl-lysophosphatidylethanolamine, some of which was further hydrolyzed to glycerophospho (N-acyl)ethanolamine.
D000818:Animals; D001921:Brain / Q000378:metabolism*; D002250:Carbon Radioisotopes; D004285:Dogs; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008861:Microsomes / Q000378:metabolism*; D010714:Phosphatidylethanolamines / Q000138:chemical synthesis / Q000378:metabolism*; D010739:Phospholipase D / Q000378:metabolism*; D010740:Phospholipases / Q000378:metabolism*; D013347:Subcellular Fractions / Q000378:metabolism; D014316:Tritium
D002250:Carbon Radioisotopes; D010714:Phosphatidylethanolamines; D014316:Tritium; D010740:Phospholipases; D010739:Phospholipase D