Objective：To compare the effects of Zn^2＋ on the P2X receptor-mediated, ATP-induced currents in neurons separated from rat superior cervical ganglion （SCG）, nodose ganglion （NG）, and otic ganglion （OTG）. Methods.. Whole-cell patch clamp recording technique was used to study the regulatory effects of Zn2＋ on ATP/αβ-me ATP-induced currents in the above 3 ganlglion neurons. Results： All SCG neurons responded to ATP with a sustained current, while no neurons responded to αβ-me ATP：Zn^2＋ potentiated ATP-induced sustained currents to （1 442±34）% of the original value. All NG neurons responded to ATP and αβ-me ATP with a similar sustained current,coapplication of Zn^2＋ （10μmol/L） potentiated their responses to （180±12） % and （262±28）% ,respectively. All OTG neurons responded to both ATP and a~-me ATP with a sustained current. Coapplication of Zn^2＋ （10μmol/L） did not significantly potentiate the sustained currents induced by 10 μmol/L ATP, but when ATP was at 30μmol/L, Zn^2＋ （10-100μmol/L） inhibited ATP-induced sustained currents in a dose dependent manner. If TNP-ATP （100 nmol/L） was first used to inhibit ATP-induced current to （26±2）% of the original value, Zn^2＋ at 10μmol/L potentiated the inhibited current to （127±9）% of its original value. Coapplication of Zn^2＋ （10μmol/L） potentiated αβ-me ATP-induced currents to （146 5± 5）% of the control. Zn^2＋ （300μmol/L） had no effect on ton and toff of ATP- and αβ-me ATP-induced （30μmol/L） currents in OTG neurons. Conclusion, （1） Zn^2＋ is an allosteric modulator of P2X2 and P2X2/3 receptors in SCG and NG neurons and can potentiate the currents they induced. （2）The predominant receptor subtypes in OTG appear to be homomeric P2X2/3 and a little P2X2. Zn^2＋ has an inhibitory effect on the ATP-induced currents in OTG neurons, suggesting some novel members of the P2X purinoceptor exist in these neurons.