Study On The Changes Of ERP And MAPK Signal Pathway In Hippocampal Of Mice With Vascular Dementia And The Effect Of Donepezil Hydrochloride

Vascular dementia (VD) is a clinical syndrome of intelligence and recognition impairment caused by cerebrovascular diseases and is called the acquired intelligence impairment syndrome. It is one of the most common diseases of neurology. With the increasing of the proportion of aged people in the population increases and the changes of diseases spectrum as well as the elevating of the diagnostic level day by day, the mobility of VD presents an obviously increase tendency, which gives a heavy threaten to the physical and mental health of the aged people. And a heavy burden of spirit and economy to the families and society. At present, the pathogenesis of VD has not been fully explained and there is not specific method for treatment, So to investigate the pathogensis of VD and search for medicine to improve intelligence use nootropics on the base of the treatment of primary disease can be hoped to improve the quality of VD patient's life.It has significant value and theory meaning.Event-related potential (ERP) is a kind of electrophysiology technique that reflect cerebral function objectively. It involve in handle process from stimulate to cognition and not contain respond determine and respond implement. It is including the process of discrimination to stimulate and save the new message after coding. It serves as auxiliary diagnosis for psyche-neuro cognition functional lesion (such as early clinic stage of dementia). It is important index to evaluate course of disease, therapeutic effect and prognosis. ERP is mainly consisting of 3 extrinsic elements P1, N1, P2 and endogenous elements, N2, P3. At present, the most of study is N2, P3 potential. Its clinical application is extremely wide.This experiment confirmed that it was a noninvasive, objective, quantitative, valuable electrophysiology detect method to undertake ERP potential mea-surement with mice by the means of insert electrode subcutaneously under un-anaesth condition. In this experiment, the mice were subjected for ischemia and reperfusion repeatedly by the ligation of bilateral common carotid arteries to establish the VD model. The behavioral changes were investigated by step-down test and water maze test. Aim of this experiment is to built up the ERP model, mensurate mode and ERP potential reference standard in mice with VD and to discuss theirs significance change characteristics of ERP of normal group, sham operated group, VD group and Donepezil group. This study certifyed that Donepezil hydrochloride can obviously improve abilitys of learning, memory and affect the ERP.Mitogen activated protein kinase (MAPK) family extensively distribute intracytoplasm, is a protein kinase with serin/threonine residue. It cans transmission Extracellular signal to celluar nucleus and is an important signal transducting system and pathway cause cytobiology reactive. MAPK family signal transduct pathway through three cascade kinase. Extracellular signal-regulated kinase (ERK) and c-JunN-terminal kinase (JNKs ) or (SAPK) , p38MAPK are members of the mitogen activated protein kinases(MAPKs) surperfamily, various extracellular signal stimulus activated different MAPK pathway, different substrate, and cause specific physiological reaction. These signal transducting pathways make up a tangles signal network interactly in vivo.The Change of their ERK, p38MAPK, JNK in neuron of hippocampus was observed with immunohistochemical and in situ hybridization. And we were performed the study of correlation analysis of change of their ERK, p38MAPK, JNK with learning and memory records. Results show that either the learning and memory records or the express of ERK, p38MAPK, JNK have a significance differencee with VD model group when compared with normal group, sham operated group and VD that treated with Donepezil hydrochloride. The learning and memory ability of VD model group is decreased; the level of p38MAPK, JNK in neuron of hippocampus is increased. They are significance negative correlation significantly, the level of ERK in neuron of hippocampus is decreased, and they are positive correlation significanly. It demonstrate that MAPK signal transducting pathway participate in the learning and memory abilitys of mice and Donepezil hydrochloride can improve the learning and memory ability.At present, the mechanisms of donepezil include: (1) Inhibit actylcholinesterase (AchE) to degrade to acetylcholine (Ach) reversability, increase quantity of Ach, Ach effect muscarinic Ach receptor (m-AchR) and activates the express of ERK, increases the abilitys of learning and memory. (2) Decrease express of subtype of NMDAR-NR1, increase NR2B express of hippocampus, and conduce to adjust learning and memory. (3) Increase cerebral blood flow, decrease amyloid neurotoxicity and neural degeneration of free radicaland so on,What is helpful for the treatment of mice with VD. (4) Donepezil can protecti electrophysiological ability of neuron by decreasing damage of pyramidal neuron, resulting in shorter ERP latency than VD mice. The study consider Donepezil can obviously improve the learning and memory ability.The aim of this experiment is to investigate the changes of ERP and the effect Donepezil, and to investigate the pathogenesis of the changes of MAPK in morbility of VD model and VD model that treated with Donepezil.1 The establishment of VD mice model and the recording learning and memory in mice with VD1.1 Objective: The aim is to establish the model of VD mice, investigate the method, and test the learning and memory ability of mice. It establishes the foundation to study the pathogenesis of VD and search for the measure to prevention and cure VD, and then evaluate them.1.2 Methods:1.2.1 The grouping of animal and the establishment of VD mice model: 306 cases male mice of 3 month (Kunming, 32.5±2.5g) were divided into the nomal group (n =78), sham operated group (n=77), VD model group (n=75), Donepezil group (n=76). The mice were subjected for ischemia-reperfusion thrice by ligating the bilateral common carotid arteries to establish the VD model. In sham operated group,their bilateral common carotid arteries were exposed and seted knots:But there was no ligation of arteries and no cerebral ischemia-reperfusion. Donepezil hydrochloride group were bred with Donepezil hydrochloride (3mg.kg-1.d-1) solution afer operation,The other mice were bred with normal saline post operation.1.2.2 The test of learning, memory of mice: In 29th day after operation, the learning of every group was tested by step-down test and water maze test. The response time (sec) and error times (number/5min) in step-down test, and the swimming time (sec) and error times (number/3min) were used to reflect achivement of learning.In 30th day after operation, the memory of every group was tested by step-down test and water maze test. The result of latency time (sec) and error times (number/5min) in step-down test and of swimming time (sec) and error times (number/3min) is the records of memory.1.3 Results:1.3.1 The test of learning of mice1.3.1.1 The results of step-down test revealed that:⑴The response time in learning phase of VD model group (84.22±14.38)s prolonged distinctly (P<0.01), compared with the response time of nomal group (53.62±23.32)s and sham operated group (50.26±20.48)s;⑵The response time of Donepezil group (55.43±25.38)s shortened distinctly (P<0.01), compared with VD model group;⑶The error time in learning phase of VD model group (3.70±0.19) increased notably (P<0.01), compared with the error time of nomal group (1.31±0.63) and sham operated group (1.25±0.33);⑷The error time of Donepezil group (1.39±0.34) decreased notably (P<0.05), compared with VD model group.1.3.1.2 The results of water maze test revealed that:⑴The swimming time in learning phase of VD model group (144.57±33.26)s prolonged distinctly (P<0.01), compared with nomal group (98.56±51.50)s and sham operated group (85.54±31.88)s;⑵The swimming time of Donepezil group (99.24±36.43)s shortened remarkably (P<0.05), compared with VD model group;⑶The error time in learning phase of VD model group (31.65±11.23) increased significantly (P<0.05), compared with nomal group (15.68±6.39) and sham operated group (16.26±7.55);⑷The error time of Donepezil group (16.56±8.91) decreased notably (P<0.01), compared with VD model group.1.3.2 The test of memory of mice1.3.2.1 The results of step-down test revealed that:⑴The latency time in memory phase of VD model group (76.36±33.23)s shortened distinctly (P<0.05), compared with the latency time of nomal group (116.71±35.78)s and sham operated group (145.36±25.21)s;⑵The latency time of Donepezil group (116.62±35.56)s prolonged significantly (P<0.05), compared with VD model group;⑶The error time in memory phase of VD model group (1.70±0.51) increased notably (P<0.05), compared with the error time of nomal group (0.80±0.34) and sham operated group (0.33±0.12);⑷The error time of Donepezil group (0.61±0.23) decreased notably (P<0.05), compared with VD model group.1.3.2.2 The results of water maze test revealed that:⑴The swimming time in memory phase of VD model group (132.80±34.32)s prolonged distinctly (P<0.05), compared with nomal group (83.68±32.43)s and sham operated group (76.45±26.84)s;⑵The swimming time of significantly Donepezil group (86.45±36.56)s shortened remarkably (P<0.05), compared with VD model group;⑶The error time in memory phase of VD model group (18.57±11.32) increased notably (P<0.05), compared with nomal group (8.96±6.12) and sham operated group (9.38±8.12);⑷The error time of Donepezil group (10.18±6.70) decreased significantly (P<0.01), compared with VD model group.1.4 Conclusions: The mice were subjected for ischemia (20min)-reperfusion (10min) thrice by ligating the bilateral common carotid arteries to establish the VD model. These studies suggested that the results of learning and memory in each group were tested by step-down test and water maze test. The records learning and memory ability of VD mice were worse than the other group. Donepezil might improve their ability. 2 The measure, significance and feature of ERP in mice with VD and the effect of donepezil on ERP2.1Objective: The purpose of the study was to built up the animal model,measuring mode and reference standard of the detection of ERP in the mice. To discuss theirs change characteristics of ERP in each group, and the effects of donepezil to it in VD mice.2.2 Methods:2.2.1 The grouping of animal and the establishment of VD mice model: 64 cases male mice of 3 month (Kunming, 32.5±2.5g) were randomly divided into the nomal group (n=16), sham operated group (n=16), VD model group (n=16), Donepezil group (n=16). The mice were subjected for ischemia (20 min)-reperfusion (10min) thrice by ligating the bilateral common carotid arteries to establish the VD model. The changes of learning and memory ability were investigated by step-down test and water maze test. The methods and results were same as part 1.2.2.2 ERP determine method: To fix the mice on stereotaxic apparatus, the frontal region skin of mice were sterilized with 75% alcohol. Recording electrodes were pricked into the point of intersection of sagittal suture and line of two auditory canal with 0.5 mm acupuncture and inclined forword about 2～3mm. Reference electrode was placed under post aurem. Ground electrode was put at prefrons. Experiment apply electromyologram evoked potential determinator, The frequency of burst sound target stimulation was 2000Hz, The probability ratio was 20%;The frequency of burst sound nontarget stimulation was 1000Hz; the probability ratio was 80%. The sound density stimulation was 120dB; the time of analysis was 500ms, overlaid 300 times in order. N2 latence, P3 latence and amplitude were recorded repeatly thrice, take average value.2.3 Result: The results of ERP determine revealed that (1) Compared with N2 latency (147±56.90)ms, P3 latency (244.40±63.15)ms of nomal group and N2 latency (165±60.66)ms, P3 latency (222.5±59.65)ms of sham operated group, N2 latency (235.03±64.61)ms, P3 latency (339.12±42.26)ms of VD model group prolonged distinctly (P<0.01). (2) The N2 latency, P3 latency of VD model group are significantly longer than the N2 latency (117.60±58.35)ms, P3 latency (249.80±50.69)ms of VD mice that treated with donepezil (P<0.01);(3) Compared with P3 amplitude (4.79±2.07)μv of nomal group and P3 amplitude (5.35±2.23)μv of sham-operation group, VD model group P3 amplitude (3.51±1.68)μv decreased distinctly (P<0.01). (4) Compared with P3 amplitude of VD model group, P3 amplitude (4.99±2.47)μv of VD with Donepezil increased notably (P<0.05).2.4 Conclusions: This experiment supply a noninvasive, objective, quantitative, valuable electrophysiology detect method to undertake ERP potential mea-surement with mice to utilize method of insert electrode subcutaneously un-anaesth condition. It confirmed that N2 latency, P3 latency of VD model group is prolonger distinctly than normal group, and sham operated group and donepezil group. P3 amplitude is lower than nomal group, sham operated group and Donepezil group. It certifies that Donepezil can obviously improve abilitys of learning, memory and effect ERP potential.3 The level of JNK in the hippocampal CA1 area of VD mice and the effect of Donepezil3.1 Objective: To explore the significance and the characteristics of Change of JNK and its mRNA in the hippocampal CA1 area of VD mice, and the effects of Donepezil.3.2 Methods:3.2.1 The grouping of animal and the establishment of VD mice model: 87 cases male mice of 3 month (Kunming, 32.5±2.5g) were randomly divided into the nomal group (n=23), sham operated group (n=21), VD model group (n=22), Donepezil group (n=21).The mice were subjected for ischemia (20 min)-reperfusion (10min) thrice by ligating the bilateral common carotid arteries to establish the VD model. The changes of learning and memory were investigated by step-down test and water maze test. The methods and results were same as part 1.3.2.2 Determination of the level of JNK in the hippocampus of mice: The mice were anaesthetized by 10% chloral hydrate solution and their brains were fixed up by 4%paraformaldehyde solution.The paraffin slices of hipocampus were made and JNK receptor was dyed through immunohistochemistry.At the same time,The expression of JNK mRNA was observed through in-situ hybridization and made the statistics of every group.We respectively counted positive cells of JNK in the same area of CAl in hippocampus (surface density Sv showing their numbers) with Image-Pro Plu software. The results were analysised with SPSS 12.0 statistics software.3.3 Result:3.3.1. Immunohistochemistry:3.3.1.1 The observed the morphous and the distribution of JNK positive cell in hippocampus:The JNK immune response positive cells in hippocampal CAl area were located mainly at cell membrane and cytoplasm. (1) The positive neurons in nomal group and sham operated group was ranged in order;The positive neurons were brown and round or ellipse. The cell bodys were comparatively large. (2) The number of JNK positive cells was obviously increase in VD model group.The arrangement of pyramidal neurons was tightly.Cells were dyed densely in VD model group. (3) The number of JNK positive cells of Donepezil group was decrease when compared with VD model group,the arrangement of pyramidal neurons was loosely and dyed lightly.3.3.1.2The level of positive cells of JNK by IHC stainning in hippocampus: (1) Compared with the surface density Sv of positive neurons of nomal group (8.35±0.71) and sham operated group (10.38±4.23), the surface density Sv of positive neurons (30.38±17.74) of VD model group was increased distinctly (P<0.01). (2) The surface density Sv of JNK positive neurons of hippocampus in Donepezil group (19.00±8.56) was decreased when compared with VD model group (P<0.05).3.3.1.3The correlation analysis of their learning and memory records with the change of JNK positive neurons of hippocampus: We were performed the study of correlation analysis of the learning and memory records with the change of the surface density Sv of JNK positive neurons of hippocampus. Results show that the response time was prolong, latence phase was shorten, error times were increase by step-down test, and the swimming time was long, the error times were increase by water maze test accompaned with the increase of JNK positive neurons of hippocampus the in each group. Following the increase of JNK positive neurons of hippocampus in each group, the learning and memory records have a significance decrease.There are correlations between them.3.3.2 In situ hybridization3.3.2.1 Observed the morphous and the distribution of JNK mRNA positive cell in hippocampus by ISH stainning:(1) The JNK mRNA positive cell in hippocampal CAl area was located mainly at cell nucleus and cytoplasm. The arrangement of pyramydal neurons in hippocampal CA1 area in nomal group and sham operated group was in order, layered clearly in light microscope; the positive neurons were brown and round or ellipse. The cell bodys were comparatively large. (2) The number of JNK mRNA positive cells was obviously increased in VD model group. The arrangement of these pyramidal neurons were tightly and not in order. Cytoplasm dyed densely in VD model group. (3) The number of JNK mRNA positive cells of Donepezil group was decreased when compared with VD model group; the arrangement of pyramidal neurons was loosely and dyed lightly. This situation was obviously improved in Donepezil group.3.3.2.2 The level of JNK mRNA positive neurons of hippocampal CA1 area by ISH stainning: (1) The surface density Sv of JNK mRNA positive neurons of hippocampus in VD model group (42.69±5.64) was increaser distinctly (P<0.05), when compared with nomal group (9.71±2.84) and sham operated group (11.84±0.91). (2) The surface density Sv of JNK mRNA positive neurons of hippocampus in Donepezil group (17.46±8.88) was decreased when compared with VD model group (P<0.01).3.3.2.3 The correlation analysis of their learning and memory records with the change of JNK mRNA positive neurons of hippocampus: We were performed the study of correlation analysis of the learning and memory records with the change of the density of JNK mRNA positive neurons of hippocampus. Results show that the response time was prolong, latence phase was shorten, error times were increase by step-down test, and the swimming time was long, the error times were increase by water maze test accompaned with the increase of JNK mRNA positive neurons of hippocampus the in each group. Following the increase of JNK mRNA positive neurons of hippocampus in each group, the learning and memory records have a significance decrease.There is a correlation between them.3.4 Conclusions: The poor grade of learning and memory in VD mice was related to the increased of JNK positive neurons of hippocampus.Donepezil can prevent the increased of JNK positive neurons of hippocampus. It certified that Donepezil can obviously improve abilitys of learning, memory in mice with VD.4 The level of the ERK 1 in the Hippocampal CA1 area in mice with VD and effects of Donepezil4.1 Objective: To explore the significance and the characteristics of change of ERK1 and its mRNA in the hippocampal CA1 area of VD mice, and the effects of Donepezil in mice with VD.4.2 Methods:4.2.1 The grouping of animal and the establishment of VD mice model: 91 cases male mice of 3 month (Kunming, 32.5±2.5g) were randomly divided into the nomal group (n=23), sham operated group (n=24), VD model group (n=21), Donepezil group (n=23). The methods to establish of the VD model and investigate changes of learning and memory by step-down test and water maze test were same as part 1.4.2.2 Determination of the level of ERK1 in the hippocampus of mice: The method to determine the level of ERK1 in the hippocampus of mice and the means of counted and analysis surface density Sv of positive cells of ERK1 was same as part 1.4.3 Result: 4.3.1 Immunohistochemistry4.3.1.1 Observed the morphous and the distribution of ERK1 positive cell in hippocampus by IHC : The ERK1 immune response positive cells in hippocampal CAl area were located mainly at cell membrane and cytoplasm. (1) The arrangement of positive pyramidal neurons in nomal group and sham operated group was ranged in order and tightly. The positive neurons were brown, large and round or ellipse. The positive neurons cytoplasm dyed densely. (2) The number of ERK1 positive cells was obviously decrease in VD model group.The arrangement of pyramidal neurons in VD model group was loosely and dyed lightly. The positive neurons were smaller. (3) The number of ERK1 positive cells of Donepezil group was increase when compared with VD model group. The arrangement of pyramidal neurons was was tightly and the positive neurons were larger in Donepezil group.4.3.1.2 The level of positive cells of ERK1 by IHC stainning in hippocampus: (1) Compared with the surface density Sv of positive neurons of nomal group (21.21±9.15) and sham operated group (21.00±7.21), the average density of positive neurons of VD model group (13.38±3.32) was decrease distinctly (P<0.01). (2) The average density of positive neurons of Donepezil group (23.31±13.26) was increased when compared with VD model group (P<0.01).4.3.1.3 The correlation analysis of their learning and memory records with the change of ERK1 positive neurons of hippocampus: we were performed the study of correlation analysis of the learning and memory records with the change of the surface density Sv of ERK1 positive neurons of hippocampus. Results show that the response time was prolong, latence phase was shorten, error times were increase by step-down test, and the swimming time was long,the error times were increase by water maze test accompaned with the decrease of ERK1 positive neurons of hippocampus the in each group. Following the decrease of ERK1 positive neurons of hippocampus in each group, the learning and memory records have a significance decrease. There are correlations between them.4.3.2 In-situ hybridization 4.3.2.1 Observed the morphous and the distribution of ERK1 mRNA positive cell in hippocampus by ISH stainning:The ERK1 mRNA positive cells in hippocampal CAl area were located mainly at cell nucleus and cytoplasm. (1) The arrangement of pyramydal neurons in hippocampal CA1 area in nomal group and sham operated group was in order, layered clearly in light microscope, The positive neurons were brown,large and round or ellipse. The positive neurons cytoplasmdyed densely. (2) The surface density Sv of ERK1 positive cells was obviously decrease in VD model group.The arrangement of pyramidal neurons in VD model group was loosely and dyed lightly. The positive neurons were smaller. (3) The surface density Sv of ERK1 positive cells of Donepezil group was increased when compared with VD model group. The arrangement of pyramidal neurons was was tightly and the positive neurons were larger in Donepezil group.4.3.2.2 The level of ERK1 mRNA positive neurons of hippocampal CA1 area by ISH stainning: (1) The surface density Sv of ERK1 mRNA positive neurons of hippocampus in VD model group (14.57±3.67) was decreased distinctly (P<0.05), when compared with nomal group (34.79±21.10) and sham operated group (34.43±18.65). (2) The surface density Sv of ERK1 mRNA positive neurons of hippocampus in Donepezil group (28.38±15.66) was increased when compared with VD model group (P<0.01).4.3.2.3 The correlation analysis of their learning and memory records with the change of ERK1 mRNA positive neurons of hippocampus: we were performed the study of correlation analysis of the learning and memory records with the change of the density of ERK1 mRNA positive neurons of hippocampus. Results show that the response time was prolong, latence phase was shorten, error times were increase by step-down test, and the swimming time was long, the error times were increase by water maze test accompaned with the decrease of ERK1 mRNA positive neurons of hippocampus the in each group. Following the decrease of ERK1 mRNA positive neurons of hippocampus in each group, the learning and memory records have a significance decrease. There are correlations between them. 4.4 Conclusions: The poor grade of learning and memory in VD mice was related to the decreased of ERK1 positive neurons of hippocampus. Donepezil can prevent the increased of ERK1 positive neurons of hippocampus. It certified that Donepezil can obviously improve abilitys of learning, memory by effect ing the level of ERK1 positive neurons of hippocampus.in mice with VD.5 The level of p38 MAPK in the hippocampal CA1 area of VD mice and the effect of Donepezil for it5.1 Objective: To explore the significance and the characteristics of Change of p38 MAPK and its mRNA in the hippocampal CA1 area of VD mice, and the effects of Donepezil.5.2 Methods:5.2.1 The grouping of animal and the establishment of VD mice model: 64 cases male mice of 3 month (Kunming, 32.5±2.5g) were randomly divided into the nomal group (n=16), sham operated group (n=16), VD model group (n=16), Donepezil group (n=16). The methods to establish of the VD model and investigate changes of learning and memory by step-down test and water maze test were same as part 1.5.2.2 Determination of the level of p38 MAPK in the hippocampus of mice: The method to determine level of p38 MAPK in the hippocampus of mice and the surface density Sv cells of p38 MAPK was same as part 1.5.3 Result:5.3.1 Immunohistochemistry:5.3.1.1 Observed the morphous and the distribution of p38 MAPK positive cell in hippocampus:The about express p38 MAPK immune response positive cell in hippocampal CAl area were located mainly at cell membrane and cytoplasm. (1) The positive neurons in nomal group and sham operated group was ranged in order;The positive neurons were brown and round or ellipse. (2) The surface density Sv of p38 MAPK positive cells was obviously increase in VD model group.The arrangement of pyramidal neurons was tightly. Cells were dyed densely in VD model group. (3) The number of p38 MAPK positive cells of Donepezil group was decreased when compared with VD model group,the arrangement of pyramidal neurons was dyed lightly.5.3.1.2The level of positive cells of p38 MAPK by IHC stainning in hippocampus: (1) Compared with the surface density Sv of positive neurons of nomal group (8.78±1.86) and sham operated group (26.67±11.64), the surface density Sv of positive neurons (71.11±27.96) of VD model group was increased distinctly (P<0.01). (2) The surface density Sv of positive neurons of Donepezil group (33.56±13.37) was decreased when compared with VD model group (P<0.01).5.3.1.3The correlation analysis of their learning and memory records with the change of p38 MAPK positive neurons of hippocampus: we were performed the study of correlation analysis of the learning and memory records with the change of the surface density Sv of p38 MAPK positive neurons of hippocampus. Results show that the response time was prolong, latence phase was shorten, error times were increase by step-down test, and the swimming time was long, the error times were increase by water maze test accompaned with the increase of p38 MAPK positive neurons of hippocampus the in each group. Following the increase of p38 MAPK positive neurons of hippocampus in each group, the learning and memory records have a significance decrease. There are correlations between them.5.3.2 In-situ hybridization5.3.2.1 Observed the morphous and the distribution of p38 MAPK mRNA positive cell in hippocampus by ISH stainning:The p38 MAPK mRNA positive cells in hippocampal CAl area were located mainly at cell nucleus and cytoplasm. (1) The arrangement of pyramydal neurons in hippocampal CA1 area in nomal group and sham operated group was in order, layer clearly in light microscope, the positive neurons were brown and round or ellipse. (2) The number of p38 MAPK mRNA positive cells was obviously increased in VD model group. The arrangement of these pyramidal neurons were tightly and not in order. Cytoplasm was dyed densely in VD model group. (3) The number of p38 MAPK mRNA positive cells of Donepezil group was decreased when compared with VD model group,The arrangement of pyramidal neurons was loosely and dyed lightly. This situation was obviously improved in Donepezil group.5.3.2.2 The level of p38 MAPK mRNA positive neurons of hippocampal CA1 area by ISH stainning: (1) The surface density Sv of p38 MAPK mRNA positive neurons of hippocampus in VD model group (71.279±5.64) was increaser distinctly (P<0.05), when compared with nomal group (12.44±5.46) and sham operated group (16.30±2.67). (2) The surface density Sv of p38 MAPK mRNA positive neurons of hippocampus in Donepezil group (33.00±17.30) was decreased when compared with VD model group (P<0.01).5.3.2.3 The correlation analysis of their learning and memory records with the change of p38 MAPK mRNA positive neurons of hippocampus: we were performed the study of correlation analysis of the learning and memory records with the change of the density of p38 MAPK mRNA positive neurons of hippocampus. Results show that the response time was prolong, latence phase was shorten, error times were increase by step-down test, and the swimming time was long, the error times were increase by water maze test accompaned with the increase of p38 MAPK mRNA positive neurons of hippocampus the in each group.Following the increase of J p38 MAPK mRNA positive neurons of hippocampus in each group, the learning and memory records have a significance decrease. There are correlations between them.5.4 Conclusions: The poor grade of learning and memory in VD mice was related to the increase of p38 MAPK positive neurons of hippocampus. The improvement of learning and memory in VD mice that treated with donepezil was related to the decrease of p38 MAPK positive neurons of hippocampal CA1. There are correlation between the expression of p38 MAPK in hippocampal CAl area with the record learning and memory of in nomal group, sham operated group, VD model group and donepezil group.