Lysophospholipase selective for N-acyl phosphatidylethanolamine (NAPE). Contributes to the biosynthesis of N-acyl ethanolamines, including the endocannabinoid anandamide by hydrolyzing the sn-1 and sn-2 acyl chains from N-acyl phosphatidylethanolamine (NAPE) generating glycerophospho-N-acyl ethanolamine (GP-NAE), an intermediate for N-acyl ethanolamine biosynthesis (PubMed:16818490, PubMed:25853435). Hydrolyzes substrates bearing saturated, monounsaturated, polyunsaturated N-acyl chains (PubMed:16818490, PubMed:25853435). Shows no significant activity towards other lysophospholipids, including lysophosphatidylcholine, lysophosphatidylethanolamine and lysophosphatidylserine (PubMed:16818490). H2O + N-hexadecanoyl-1,2-di-(9Z-octadecenoyl)-sn-glycero-3-phosphoethanolamine = (9Z)-octadecenoate + H(+) + N-hexadecanoyl-1-(9Z-octadecenoyl)-sn-glycero-3-phosphoethanolamine H2O + N-acyl-1,2-diacyl-sn-glycero-3-phosphoethanolamine = a fatty acid + H(+) + N,1-diacyl-sn-glycero-3-phosphoethanolamine H2O + N-hexadecanoyl-1-(9Z-octadecenoyl)-sn-glycero-3-phosphoethanolamine = (9Z)-octadecenoate + H(+) + N-hexadecanoyl-sn-glycero-3-phosphoethanolamine H2O + N-octadecanoyl-1-(9Z-octadecenoyl)-sn-glycero-3-phosphoethanolamine = (9Z)-octadecenoate + H(+) + N-octadecanoyl-sn-glycero-3-phospho-ethanolamine H2O + N-eicosanoyl-1-(9Z-octadecenoyl)-sn-glycero-3-phosphoethanolamine = (9Z)-octadecenoate + H(+) + N-eicosanoyl-sn-glycero-3-phosphoethanolamine H2O + N,1-di-(9Z-octadecenoyl)-sn-glycero-3-phosphoethanolamine = (9Z)-octadecenoate + H(+) + N-(9Z-octadecenoyl)-sn-glycero-3-phosphoethanolamine H2O + N-(5Z,8Z,11Z,14Z-eicosatetraenoyl)-1-(9Z-octadecenoyl)-sn-glycero-3-phosphoethanolamine = (9Z)-octadecenoate + H(+) + N-(5Z,8Z,11Z,14Z-eicosatetraenoyl)-sn-glycero-3-phosphoethanolamine 1-octadecanoyl-2-(9Z-octadecenoyl)-sn-glycero-3-phospho-(N-hexadecanoyl)-serine + H2O = (9Z)-octadecenoate + 1-octadecanoyl-2-hydroxy-sn-glycero-3-phospho-(N-hexadecanoyl)-serine + H(+) 1-(1Z-octadecenoyl)-2-(9Z-octadecenoyl)-sn-glycero-3-phospho-N-hexadecanoyl-ethanolamine + H2O = (9Z)-octadecenoate + 1-O-(1Z-octadecenyl)-sn-glycero-3-phospho-N-hexadecanoyl-ethanolamine + H(+) H2O + N,1-diacyl-sn-glycero-3-phosphoethanolamine = a fatty acid + H(+) + N-acyl-sn-glycero-3-phosphoethanolamine Highest levels in the CNS and in testis, intermediate levels in liver and kidney. Hardly detectable in heart. Homozygous knockout ABHD4 mice are born at the expected Mendelian frequency, are viable and healthy, and show no overt differences in their cage behavior compared to that of wild-type littermates. Belongs to the peptidase S33 family. ABHD4/ABHD5 subfamily. Thr-291 is present instead of the conserved His which is expected to be an active site residue.