Regulatory role of E-NTPase/E-NTPDase in Ca(2+)/Mg(2+ )transport via gated channel

BACKGROUND: E-NTPase/E-NTPDase is activated by millimolar concentrations of Ca(2+ )or Mg(2+ )with a pH optimum of 7.5 for the hydrolysis of extracellular NTP and NDP. It has been generally accepted that E-NTPase/E-NTPDase plays regulatory role in purinergic signalling, but other functions may yet be discovered. RESULTS: In this article it is proposed on the basis of published data that E-NTPase/E-NTPDase could play a role in the influx and efflux of Ca(2+)and Mg(2+ )in vivo. CONCLUSIONS: Attenuation of extracellular Ca2+ influx by rat cardiac sarcoplasmic anti-E-NTPase antibodies and oligomerization studies on mammalian CD39 conclusively point towards the existence of a new channel in the membrane. Further studies on these properties of the E-NTPase/E-NTPDase may provide detailed mechanisms and identify the potential patho-physiological significance.