The function of ENSG00000138185 (ENTPD1, ectonucleoside triphosphate diphosphohydrolase 1) is as follows. Catalyzes the hydrolysis of nucleoside triphosphates (NTPs) and diphosphates (NDPs) (Probable) (PubMed:8529670, PubMed:8626624, PubMed:8955160, PubMed:8996251). The enzyme sequentially removes phosphate groups in two successive steps, converting NTPs to nucleoside monophosphates (NMPs) via NDP intermediates (Probable) (PubMed:8529670, PubMed:8626624, PubMed:8955160, PubMed:8996251). This activity contributes to the regulation of extracellular levels of nucleotides (Probable) (PubMed:8529670, PubMed:8626624, PubMed:8955160, PubMed:8996251). By hydrolyzing proinflammatory ATP and platelet- activating ADP to AMP, it blocks platelet aggregation and supports blood flow (PubMed:8955160, PubMed:8996251). {ECO:0000269|PubMed:8529670, ECO:0000269|PubMed:8626624, ECO:0000269|PubMed:8955160, ECO:0000269|PubMed:8996251, ECO:0000305|PubMed:10636909}.