佐替平对家兔齿状回兴奋性突触反应和长时程增强的影响

Objective To observe the impact of zotepine on the excitatory synaptic response and long term potentiation (LTP) of dentate gyrus neurons.Methods Male rabbits ( n = 20) weighting about 2.5 ～ 3.5 kg were divided into four groups randomly ( n = 5 ): control, zotepine 1.0, zotepine 2.0 and zotepine 5.0.To each rabbit,there were 60 results during 120 min.Population spike(PS) amplitude and excitory postsynaptic potential (EPSP) slope were used to be the indexes of the excitatory synaptic response of dentate gyrus neurons.The sequence was base response ( at the beginning), intraperitoneal injection of 0.5ml dimethylsulfoxide or 0.5ml zotepine-dimethylsulfoxide solution ( 1.0,2.0,5.0 mg/kg of zotepine dosage) ( after 30 min) and titanic stimulation (after 90 min).Results To 4 groups,the PS amplitude and EPSP slope after single stimuli were not significantly different from those before single stimuli.In control group, the PS amplitude and EPSP slope after titanic stimulation[(0.68 ± 0.052)mV and(0.633 ± 0.024 )mV/ms] were significantly different from those before injection[(0.266 ±0.008) mV and(0.246 ±0.010) mV/ms] (P＜0.05 ～0.01 ) ,and LTP were induced.LTP were not induced after titanic stimulation in group zotepine 1.0,2.0 and 5.0.After titanic stimulation, the PS amplitude and EPSP slope in group zotepine 5.0[(0.277 ±0.008)mV and(0.296 ±0.007) mV/ms] were significantly different from those in group control(P＜ 0.05).Conclusion Zotepine had little effect on the excitatory synaptic response of dentate gyrus neurons after single stimuli in perforant path, while it blocked the induction of LTP in perforant path-dentate gyrus pathway.

The impact of zotepine on the excitatory synaptic response and long-term potentiation in the hippocampus of rabbits