Objective To investigate the changes in regional cerebral blood flow and its relationship with atrophy of the entorhinal cortex in patients with amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD).Methods Twenty eight patients including ten cases with aMCI,nine case with mild AD and nine cases with moderate to severe AD were enrolled.The cognitive function was evaluated by revised version of Hasegawa's Dementia Scale (HDS-R) and Alzheimer's Disease Assessment Scale-cognitive part (ADAS-cog).Regional cerebral blood flow was evaluated by 99mTc-ECD SPECT and easy Z score imaging system (eZIS).Z scores of voxel-based specific regional analysis system for Alzheimer's disease (VSRAD) were used to assess the degree of atrophy of the entorhinal cortex.Results The Z-score in eZIS was lower in mild to severe AD group than in aMCI group [(1.57±0.46),(1.50±0.54) vs.(1.00±0.50),F=4.58,P=0.022],which showed that the regional cerebral blood flow of cingulate was lower in AD group than in aMCI group.The Z-score in eZIS in bilateral frontal lobes and left hippocampus were higher in moderate to severe AD group than those in aMCI group than in aMCI and mild AD group respectively [(1.43± 0.79) vs.(0.67±0.50),(0.88±0.64); (1.43±0.79) vs.(0.67±0.50),(0.75±0.46); (1.86± 0.50) vs.(1.33±0.50),(1.75±0.46),F=2.90,3.81 and 3.06,respectively,P=0.077,0.039 and 0.068],which showed that the regional cerebral blood flow of bilateral frontal lobes and left hippocampus were lower in moderate to severe AD group than in aMCI group.The score of HDS-R had a negative correlation (r =-0.568,-0.481,P=0.004,0.017) and the score of ADAS-cog had a positive correlation (r=0.462,0.459; P =0.030,0.032) with regional cerebral blood flow in hippocampus.Conclusions The regional cerebral blood flow of cingulate gyrus is decreased in early stage of AD,and involves in frontal lobe and hippocampus along with the deterioration of diseases.The changes of cognitive function are correlated with cerebral blood flow in hippocampus.The Z-score in eZIS can effectively evaluate the changes of regional cerebral blood flow in aMCI and AD patients.

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.