Zn^(2+)对兔离体颈上交感神经节的作用

EFFECTS OF Zn^(2+) ON ISOLATED SUPERIOR CERVICAL SYMPATHETIC GANGLION OF RABBITS

用蔗糖-间隙法研究了Zn^(2+)对兔离体颈上交感神经节的作用。Zn^(2+)对神经节动作电位产生浓度依赖性抑制作用,IC_(50)为1.48mmol/l。其作用在高〔Ca^(2+)〕溶液中减弱,在低〔Ca^(2+)〕溶液中加强。新斯的明、L—半胱氨酸能拮抗Zn^(2+)的抑制作用。Zn^(2+)对神经节N波也产生浓度依赖性抑制作用,对P波抑制作用很弱,对LN波无明显影响。

The effects of Zn^(2+) on the isolated superior cervical sympathetic ganglion of rabbit were stud ied with sucrese-gap method. It was found thatZn^(2+) significantly inhibited ganglienic action poten-tial with a manner of concentration-dependence.The IC-50 value was 1. 48 mmol/L. The effects ofZn^(2+) were antagonized by neostigmine and 1-cys-tein, reduced under high concentration of Ca^(2+) andenhanced under low concentration of Ca^(2+). It wasalso found that Zn^(2+) inhibited ganglionic N wave,less affected p wave and without any effect on LNwave.