钙调神经磷酸酶（calcineurin,CN）被认为在突触可塑性及在海马长时程增强（long term potentiation,LTP）中发挥了一定的作用.在两种整体LTP模型的基础上,观察了CN特异性抑制剂环胞菌素A（cyclosporin A,CsA）对大鼠海马齿状回LTP的影响.CsA能部分阻断高频刺激诱发的LTP,但它只减小了群峰电位（population spikes,PS）幅度的增加,对PS潜伏期的缩短没有影响.另一方面,CsA能完全阻断人参皂甙诱发的LTP,不仅抑制了PS幅度的增加,也阻断了PS潜伏期的缩短.结果提示,突触后神经元的CN在海马LTP的诱发过程中起着重要的作用. Calcineurin (CN) is thought to play a role in synaptic plasticity and long term potentiation (LTP) in the hippocampus.On the basis of two global LTP models, CN The effect of cyclosporin A (CsA), a specific inhibitor, on LTP of hippocampal dentate gyrus in rats.CsA partially blocked the high frequency stimulation-induced LTP, but only reduced the population spikes , PS) had no effect on the shortening of PS latency.On the other hand, CsA could completely block ginsenoside-induced LTP, which not only inhibited the increase of PS amplitude but also blocked the shortening of PS latency.Results showed that, CN of postsynaptic neurons plays an important role in the induction of LTP in hippocampus.