E - NTPDases ( Ecto - Nucleoside Triphosphate Diphosphohydrolase family , E - phosphohydrolase ATP) , previously called ecto- ATPases and ecto- apirazami , are enzymes which, in the presence of millimolar concentrations of extracellular divalent cations hydrolyze the tri- and diphosphonucleosides . Much evidence indicates that the E - NTPDases are involved in the transmission of information with ATP and P2 purynoreceptorów . The E phosphohydrolases ATP - neurotransmission is not limited to the removal of P2 receptor agonists . These enzymes by maintaining a balance between the concentration of ATP and adenosine also regulate the speed and intensity of the response of cells to purinergic signal . Lack of [ ATP] : [E -adenosine ] can lead to many serious diseases . So far it is not clear sense of occurrence in areas of synaptic E - NTPDases 2 In our opinion , this enzyme is involved in lowering high ATP concentrations in the synapse , and the creation of another neurotransmitter ATP - ADP .