Objective:To investigate the predictive value of serum matrix metalloproteinase-9 (MMP-9), fatty acid-binding protein 5 (FABP5) combined with MRI for the efficacy and recurrence of primary liver cancer after percutaneous radiofrequency ablation.Methods:A total of 192 patients with primary liver cancer who underwent percutaneous radiofrequency ablation treatment at the First Affiliated Hospital of Air Force Medical University from June 2022 to May 2023 were selected as the research subjects. MRI examination was performed within one week before the treatment, and the apparent diffusion coefficient (ADC) value was recorded. The enzyme-linked immunosorbent assay (ELISA) was used to determine the levels of MMP-9 and FABP5 in the serum. According to the results of MRI examination, the ablation status of the lesions was determined, and the patients were divided into a complete ablation group ( n=157) and a residual lesion group ( n=35). Patients with completely ablated lesions were regularly followed up for one year, and their recurrence status was recorded. According to the recurrence of the patients, the patients were divided into a non-recurrence group ( n=115) and a recurrence group ( n=42). The levels of MMP-9 and FABP5 and the ADC values of the patients in the complete ablation group and the residual lesion group, as well as those in the non-recurrence group and the recurrence group, were compared. The receiver operator characteristic (ROC) curve was used to evaluate the predictive value of serum MMP-9 and FABP5 combined with MRI for the postoperative efficacy and recurrence of the patients. Results:The levels of serum MMP-9 and FABP5, and the ADC value of patients in the complete ablation group were (181.05±29.68) ng/ml, (7.95±1.82) μg/L, and (1.32±0.45) ×10 -3 mm 2/s, respectively, while those in the residual lesion group were (202.18±35.06) ng/ml, (9.56±2.39) μg/L, and (0.75±0.23) ×10 -3 mm 2/s, respectively. The levels of MMP-9 and FABP5 in the complete ablation group were significantly lower than those in the residual lesion group, and the ADC value was significantly higher than that in the residual lesion group, with statistically significant differences ( t=3.68, P<0.001; t=4.45, P<0.001; t=7.27, P<0.001). The areas under the curve (AUC) of serum MMP-9, FABP5, and ADC value alone in predicting the postoperative efficacy of patients were 0.68 (95% CI: 0.61-0.75), 0.75 (95% CI: 0.68-0.81), and 0.90 (95% CI: 0.85-0.94), respectively. The AUC of the combined prediction of these three was 0.94 (95% CI: 0.89-0.97), and the combined prediction of these three was superior to the individual prediction of MMP-9, FABP5, and ADC value ( Z=5.72, P<0.001; Z=4.84, P<0.001; Z=2.29, P=0.022). The levels of serum MMP-9 and FABP5, and the ADC value of patients in the non-recurrence group were (176.52±30.28) ng/ml, (8.69±1.92) μg/L, and (1.35±0.29) ×10 -3 mm 2/s, respectively, while those in the recurrence group were (201.85±28.72) ng/ml, (11.05±2.86) μg/L, and (1.14±0.12) ×10 -3 mm 2/s, respectively. The levels of serum MMP-9 and FABP5 of patients in the non-recurrence group were significantly lower than those in the recurrence group, and the ADC value was significantly higher than that in the recurrence group, with statistically significant differences ( t=4.70, P<0.001; t=5.93, P<0.001; t=4.55, P<0.001). The AUCs of serum MMP-9, FABP5, and ADC value alone in predicting the postoperative recurrence of patients were 0.74 (95% CI: 0.66-0.81), 0.90 (95% CI: 0.84-0.94), and 0.74 (95% CI: 0.66-0.80), respectively. The AUC of the combined prediction of these three was 0.95 (95% CI: 0.90-0.98), and the combined prediction of these three was superior to the individual prediction of MMP-9, FABP5, and ADC value ( Z=5.00, P<0.001; Z=3.03, P=0.002; Z=5.33, P<0.001) . Conclusions:The levels of serum MMP-9 and FABP5 in patients with primary liver cancer treated by percutaneous radiofrequency ablation in the complete ablation group are significantly lower than those in the residual lesion group, and the ADC value is significantly higher than that in the residual lesion group. The levels of serum MMP-9 and FABP5 of patients in the non-recurrence group are also significantly lower than those in the recurrence group, and the ADC value is also significantly higher than that in the recurrence group. The combined detection of serum MMP-9, FABP5 and MRI has a relatively high clinical value in predicting the efficacy and recurrence of patients after percutaneous radiofrequency ablation for liver cancer.

Objective To establish a stable and reproducible animal model of abdominal intestinal firearm penetrating injury in a cold high-altitude environment.Methods Twenty landrace pigs were randomly and equally assigned to a low-altitude normal temperature(LN)group and a high-altitude cold(HC)group.The HC group was placed in a cold environment at high altitudes,and the LN group was placed in a normal-temperature environment at low altitudes.They were raised for 48 hours respectively.After anesthesia,they were suspended on the shooting range,and the right lower abdomen of the experimental pigs was shot with a gun.After injury,they were simply bandaged and transported back to the laboratory for observation in the normal temperature environment of the low altitudes.The vital signs and injuries at 0,2,4,8,12 and 24 h and 24 h survival rates of experimental pigs were compared.Laparotomy was immediately performed on the dead pigs and the experimental pigs still alive at 24 h to explore the injuries and observe the pathology of the small intestine and colon.Results The 24 h survival rate of the HC group was 70％,with no statistically significant difference compared to the LN group's 90％(P＞0.05).After the injury,the body temperature of both groups gradually increased.The body temperature of the HC group was significantly higher than the LN group at 0,2,4 and 8 h time points(P＜0.001),and the LN group exceeded the HC group at 24 h(P＜0.05).Both groups showed an initial increase followed by a decrease in heart rate,with the HC group significantly higher than the LN group only at 0 h(P＜0.01),and no statistically significant differences were observed at other time points(P＞0.05).Both groups showed an early increase and later decrease in respiratory rate,with the HC group higher than the LN group at 0,4,8,12 and 24 h(P＜0.05 or P＜0.001).There was no statistically significant difference(P＞0.05)between the HC group and the LN group in small intestine rupture,small intestine contusion,mesenteric injury,colon rupture and wound diameter.The pathology of the small intestine and colon in the HC group showed extensive necrosis and shedding of the mucosa layer,severe congestion and edema of the submucosa,and extensive lymphocyte infiltration.The LN group also showed similar symptoms but to a lesser extent.Conclusion This study established a pig model of abdominal firearm intestinal perforation injury in a cold environment at high-altitudes.The model has strong operability and stable damage,which can provide a reference for subsequent research.

Objective:To explore the early coagulation function changes of penetrating intestinal firearm injury of pig in high-altitude environments.Methods:Twenty healthy long white piglets were selected and divided into the plain group and the high-altitude group using the random number table method, with 10 pigs in each group. Pigs in the plain group were placed in a plain environment at an altitude of 800 meters, while pigs in the high-altitude group were placed in an experimental chamber simulating an altitude of 6 000 meters for 48 hours. Both groups received pistol gunshot to have firearm penetrating wounds to the abdominal intestinal tract and then returned to the plain observation room. At 0, 2, 4, 8, 12 and 24 hours after injury, coagulation in the peripheral blood and fibrinolytic indexes [prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), fibrinogen (Fbg), D-dimer (D-D), and fibrinogen degradation product (FDP)], thromboelastogram (TEG) [reaction time (R), clotting time (K), clot formation rate (α), maximum amplitude (MA) and coagulation composite index (CI) ], platelet parameters [platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW), and platelet-large cell ratio (P-LCR)] in the two groups were detected separately.Results:The PT values at 0 and 2 hours after injury in the high-altitude group were significantly lower than those in the plain group, while they were significantly higher at 8, 12 and 24 hours than those in the plain group ( P<0.01); there was no significant difference at 4 hours between the two groups ( P>0.05). The APTT values at 0, 2 and 4 hours after injury in the high-altitude group were significantly lower than those in the plain group, while they were significantly higher at 8, 12 and 24 hours after injury than those in the plain group ( P<0.01). The TT values at 0, 2 and 4 hours after the injury in the high-altitude group were significantly lower than those in the plain group, while they were significantly higher at 12 and 24 hours after injury than those in the plain group ( P<0.01); there was no significant difference at 8 hours after injury between the two groups ( P>0.05). The Fbg, D-D and FDP values at 0, 2, 4, 8, 12 and 24 hours after injury were higher in the high-altitude group than those in the plain group ( P<0.01). The R values at 0, 2 and 4 hours after injury in the high-altitude group were significantly lower than those in the plain group, while they were significantly higher at 8, 12 and 24 hours after injury than those in the plain group ( P<0.01). The K values at 0, 2, 4 and 8 hours after injury in the high-altitude group were significantly lower than those in the plain group, while they were significantly higher at 12 and 24 hours after injury than those in the plain group ( P<0.05 or 0.01). The α angles at 0, 2 and 4 hours after injury in the high-altitude group were significantly higher than those in the plain group, while they were significantly lower at 8, 12 and 24 hours after injury than those in the plain group ( P<0.01). The MA values at 0, 2 and 4 hours after the injury in the high-altitude group were significantly higher than those in the plain group, while they were significantly lower at 8, 12 and 24 hours after injury than those in the plain group ( P<0.01). The CI values at 0, 2 and 4 hours after injury in the high-altitude group were significantly higher than those in the plain group, while they were significantly lower at 8, 12 and 24 hours after injury than those in the plain group ( P<0.01). The PLT values at 0, 2, 4 and 8 hours after injury in the high-altitude group were significantly higher than those in the plain group, while they were significantly lower at 12 and 24 hours after injury than those in the plain group ( P<0.05 or 0.01). The MPV values at 0, 2, 4, 8, 12 and 24 hours after injury in the high-altitude group were significantly higher than those in the plain group ( P<0.01). The PDW values at 2, 4, 8, 12 and 24 hours after injury in the high-altitude group were significantly higher than those in the plain group ( P<0.05 or 0.01), while there was no significant difference in PDW at 0 hour after injury between the two groups ( P>0.05). The P-LCR values at 0, 2, 4, 8, 12 and 24 hours after injury in the high-altitude group were all significantly higher than those in the plain group ( P<0.01). Conclusion:Compared with the plain environments, pig intestinal firearm penetrating injury in the high-altitude environments is more prone to early hypercoagulable state accompanied by mild hyperfibrinolysis, and faster to reach a hypocoagulable state accompanied by obvious hyperfibrinolysis.

Background With the rapid industrialization, cadmium has become a primary heavy metal pollutant in cultivated land soil in China, which seriously affects human health. Previous studies have found that cadmium exposure associates with cognitive dysfunction in individuals, but there is a lack of research on the mechanism of cadmium exposure associated cognitive impairment in offspring in early life which is more vulnerable to various toxins and crucial for development of the neuro. Objective To explore the potential mechanism of brain-derived neurotrophic factor/tyrosine kinase receptor B (BDNF-TrkB) signaling pathway in cognitive dysfunction in mice after cadmium exposure in early-life. Methods Twelve 8-week-old C57BL/6 pregnant mice were randomly divided into 2 groups, namely control group and cadmium exposure group, with 6 mice in each group. The exposure period was from pregnancy day 4.5 to lactation day 21 (E4.5-P21), during which distilled water or cadmium chloride solution (2.5 mg·kg⁻¹·d⁻¹) was given. After lactation, the offspring of the control group and the cadmium exposure group were given distilled water until 8 weeks of age. Then the toxicity effects of cadmium exposure on mice were evaluated by body weight and selected biochemical indicators. The cadmium content in brain was detected and the learning and memory ability was tested by Y maze and Morris water maze to evaluate cognitive function of offspring mice. Histopathological changes of the hippocampus were observed after Nissl staining and Golgi staining. The mRNA and protein expression levels of the BDNF-TrkB pathway and synapse were detected by real-time quantitative PCR (qPCR) and Western blot. Results Compared with the control group, no significant change was found in body weight, liver or kidney function in the cadmium exposure group (P> 0.05). However, compared with the control group, the cadmium content in brain was increased in the cadmium exposure group (P<0.001). The behavioral changes associated with cognitive dysfunction were positive in the cadmium exposure group (all P<0.05). The histopathological observation after Nissl staining showed abnormal tissue structure, decreased number of neurons and increased karyopyknosis in the cadmium exposure group (P<0.01).The spine density of Golgi staining was decreased in the cadmium exposure group (P<0.001). The BDNF-TrkB pathway-related mRNA and the synapse-related mRNA in the hippocampus were reduced in the cadmium exposure group (all P<0.05). The expression levels of BDNF-TrkB pathway-related proteins and synapse-related proteins in the hippocampus were also reduced in the cadmium exposure group (P<0.05). Conclusion Early-life cadmium exposure may induce synaptic dysplasia and lead to cognitive dysfunction by down-regulating the BDNF-TrkB signaling pathway in mice.

Objective To observe the effects of electroacupuncture on the motor function and expressions of Irisin,Decorin and Myostatin in skeletal muscle of SAMP8 mice;To explore the mechanism of electroacupuncture in the treatment of the motor dysfunction of Alzheimer disease(AD).Methods Totally 247-month-old male SAMP8 mice were randomly divided into model group and electroacupuncture group,with 12 mice in each group,and the 12 male SAMR1 mice with the same age were set as the control group."Baihui","Dazhui"and"Shenshu"were selected in the electroacupuncture group,once a day,8 days as one course of treatment,with an interval of 2 days,for a total of 3 courses.The control group and the model group were not intervened.The motor function of mice was tested by grip strength test,pole climbing test and open field test,the mRNA expressions of Irisin,Decorin and Myostatin in quadriceps muscle were detected by RT-qPCR,and the protein expressions of Irisin,Decorin and Myostatin in quadriceps muscle were detected by immunohistochemistry and Western blot.Results Compared with the control group,the grip peak and duration of the mice in the model group decreased,head turning time and pole climbing time were prolonged(P<0.01),the mRNA and protein expressions of Irisin and Decorin decreased(P<0.05,P<0.01),and the expressions of Myostatin mRNA and protein increased(P<0.05).Compared with the model group,the grip peak and duration of the mice in the electroacupuncture group increased,head turning time and pole climbing time were decreased(P<0.05),the mRNA and protein expressions of Irisin and Decorin increased(P<0.05),and the expressions of Myostatin mRNA and protein decreased(P<0.05).Conclusion Electroacupuncture can improve the motor dysfunction of SAMP8 mice,and its mechanism may be related to regulating the expressions of Irisin,Decorin and Myostatin in skeletal muscle.

Objective To observe the changes to,and possible mechanism of,intestinal permeability in pigs without direct injury after an abdominal-and intestinal-penetrating injury from firearms in cold environment at high altitudes.Methods Fifty-five experimental pigs were divided into two groups:high-altitude cold group(HC)and low-altitude normal temperature group(LN).According to the observation time,each group was divided into five experimental subgroups:0h,2h,4 h,8h,and 24 h.There were six pigs in each HC subgroup and five pigs in each LN subgroup.After euthanasia,intestinal tissues were taken,and the levels of the inflammatory factors TNF-α,and IL-6 in intestinal homogenate and the concentrations of intestinal permeability-related proteins DAO and D-lactate acid in blood were detected by ELISA method.The intestinal tissues of experimental pigs were taken at 0 h and 8 h for LN and 8 h for HC,and intestinal pathological changes were observed and scored after HE staining.The concentrations of Occludin,ZO-1,Claudin-3,TLR4,NF-κB,and MLCK(proteins related to intestinal permeability)were detected by Western blot to explore the effect of a cold environment at high altitude on secondary intestinal permeability changes after injury and the possible mechanisms.Results Both the HC group and LN group experienced typical abdominal intestinal penetrating injuries,and there were no significant differences in their abdominal infection scores or intestinal adhesion(P＞0.05).The levels of DAO and D-LA in the serum of experimental pigs in the HC and LN groups gradually increased over time.The levels of DAO and D-LA in the HC group were significantly higher than those in the LN group at all time points(P＜0.01 or P＜0.001).The fastest increase in DAO and D-LA in the HC group was 4 h to 8 h,while in the LN group,it was 8 h to 24 h.The pathological score of intestinal tissue in the HC group was significantly higher than that in the LN group of experimental pigs(P＜0.01).The inflammatory factors TNF-α and IL-6 both increased over time in the intestinal tissue of LN and HC groups.The most significant time point for a increase of inflammatory factors in the HC group was 4 h to 8 h,while in the LN group,it was 8 h to 24 h.The intestinal tissue IL-6 and TNF-α levels of experimental pigs in the HC group were higher than those in the LN group the entire time(P＜0.05,P＜0.01,or P＜0.001).The levels of occludin and ZO-1 in the HC group at 8 h decreased significantly compared to those of the LN group at the 8 h time point(P＜0.05),while claudin-3 showed a significant decrease in LN(P＜0.001).In the HC group,TLR4,NF-κB,and MLCK were both higher than those in the LN group at 8 h,and the difference was statistically significant(P＜0.05).Conclusions A high-altitude cold environment can lead to a secondary increase in intestinal permeability after abdominal-penetrating firearm injury,and its mechanism may be related to the TLR4/NF-κB/MLCK pathway.

Objective: We aimed to determine the epidemiological characteristics of asymptomatic AF in elder community population (≥65 years old) to analyze the detection rate of different screening methods. Methods: The study was a prospective cohort study. The elder (≥65 years old) residents who voluntarily participated in free physical examination in Dalian community were selected. The participants were randomly divided into screening group (including intensive screening group and single screening group) and control group. The control group received interrogation, medical history collection and routine 12-lead electrocardiogram (ECG) examination. Screening group received an additional single-lead ambulatory ECG equipment worn for 5-7 days. Intensive screening group received two equal-length wearings in 2020 and 2021 respectively, while one screening group only wore once in 2020. Results: Finally 3 340 residents ((70.7±5.0) years old) which consisted of 1 488 males (44.55%) were enrolled. There were 1 945 residents in screening group, including 859 in intensive screening group and 1 086 in one-time screening group. The control group included 1 395 people. Detection rate of asymptomatic AF was significantly higher in screening group than control group (79(4.06%) vs. 24(1.72%), P<0.001). Higher detection rate was found in screening group than control group in AF risk factors (1 or 2-3) subgroups and CHA₂DS₂-VASc score (2-3 or≥4) subgroups (P<0.05). Additionally, no difference was found between intensive screening group and single screening group (42(4.89%) vs. 37(3.41%), P=0.100). Intensive screening increased detection rate (7(6.93%) vs. 1(0.58%), P=0.009) only in residents those with low thrombosis risk (CHA₂DS₂-VaSc<2). Conclusions: Screening in elderly (≥65 years old) can significantly improve the detection rate of asymptomatic AF by wearing single lead dynamic ECG device. The rate increased significantly with the increase of risk factors associated with AF by single screening. In addition, repeat screening of the same method may only improve detection rates in the group with low risk thrombotic scores and non-combination of AF risk factors.Screening methods that are appropriate for different populations may require further exploration.
Male ; Humans ; Aged ; Atrial Fibrillation/epidemiology* ; Prospective Studies ; Electrocardiography ; Risk Factors ; Stroke ; Risk Assessment ; Mass Screening/methods*

Objective: We aimed to determine the epidemiological characteristics of asymptomatic AF in elder community population (≥65 years old) to analyze the detection rate of different screening methods. Methods: The study was a prospective cohort study. The elder (≥65 years old) residents who voluntarily participated in free physical examination in Dalian community were selected. The participants were randomly divided into screening group (including intensive screening group and single screening group) and control group. The control group received interrogation, medical history collection and routine 12-lead electrocardiogram (ECG) examination. Screening group received an additional single-lead ambulatory ECG equipment worn for 5-7 days. Intensive screening group received two equal-length wearings in 2020 and 2021 respectively, while one screening group only wore once in 2020. Results: Finally 3 340 residents ((70.7±5.0) years old) which consisted of 1 488 males (44.55%) were enrolled. There were 1 945 residents in screening group, including 859 in intensive screening group and 1 086 in one-time screening group. The control group included 1 395 people. Detection rate of asymptomatic AF was significantly higher in screening group than control group (79(4.06%) vs. 24(1.72%), P<0.001). Higher detection rate was found in screening group than control group in AF risk factors (1 or 2-3) subgroups and CHA₂DS₂-VASc score (2-3 or≥4) subgroups (P<0.05). Additionally, no difference was found between intensive screening group and single screening group (42(4.89%) vs. 37(3.41%), P=0.100). Intensive screening increased detection rate (7(6.93%) vs. 1(0.58%), P=0.009) only in residents those with low thrombosis risk (CHA₂DS₂-VaSc<2). Conclusions: Screening in elderly (≥65 years old) can significantly improve the detection rate of asymptomatic AF by wearing single lead dynamic ECG device. The rate increased significantly with the increase of risk factors associated with AF by single screening. In addition, repeat screening of the same method may only improve detection rates in the group with low risk thrombotic scores and non-combination of AF risk factors.Screening methods that are appropriate for different populations may require further exploration.
Male ; Humans ; Aged ; Atrial Fibrillation/epidemiology* ; Prospective Studies ; Electrocardiography ; Risk Factors ; Stroke ; Risk Assessment ; Mass Screening/methods*

Abstract According to the Healthy China Action Plan, Wuhan gives full play to the role of preventing and controlling student myopia by promoting student health. The primary focus is placed on education in schools, and Wuhan has integrated educational resources to develop a multi-level myopia prevention and control system and service network for school students. The network contains educational adminstrative, schools, families, and professional technical service organizations. By integrating multiple disciplines, Wuhan has built a comprehensive vision health management service system for all students. The Internet and cloud intelligent monitoring facilitated the establishment of a smart vision health management platform for students, which thoroughly and efficiently implemented myopia prevention and control to safeguard students visual health by engaging in education, monitoring, and supervision. The prevention and control of student myopia is a breakthrough for comprehensive healthy development of students. A comparison of the standard myopia rate in Wuhan in 2019 and 2018 revealed that the standard myopia rate at different learning stages of primary school, junior high school, and high school dropped by 3.31, 2.50, and 2.26 percentage points, respectively, and the rate of myopia in primary school was significantly lower than the national level. Post-epidemic surveys showed that the compliance rate and the awareness rate of the visual environment and visual behaviors of primary and secondary school students in Wuhan reached more than 80%, and prevalence of newly onset myopia or decreased vision was 30%, which was lower than the national average. The "Wuhan Model" provides an important referential framework for public health services for school students.

Objective:To evaluate the effect of melatonin on prefrontal cortex ischemia-induced cognitive impairment in rats and to investigate the receptor mechanism.Methods:Clean-grade adult male Sprague-Dawley rats, weighing 300 g, were selected, and a catheter was implanted into the prefrontal cortex.The experiment was performed in two parts.Experiment Ⅰ Twenty-four rats, in which catheters were successfully inserted into the prefrontal cortex, were assigned into 3 groups ( n=8 each) using a random number table method: control group (group C), model group (group M) and melatonin group (group ME). Normal saline 0.5 μl was injected into the prefrontal cortex in group C, 1 μmol/L endothelin 0.5 μl was microinjected into the prefrontal cortex in group M, and 1 μmol/L endothelin and 1 μmol/L melatonin 0.5 μl were injected into the prefrontal cortex in group ME.Experiment Ⅱ Forty-four rats, in which catheters were successfully inserted into the prefrontal cortex, were assigned into 4 groups ( n=11 each) using a random number table method: model group (group M), melatonin group (group ME), MT 1/2R antagonist luzindole + melatonin group (group L + ME) and MT 2R antagonist 4p-pdot + melatonin group (group P + ME). In group M, 1 μmol/l endothelin 0.5 μl was microinjected into the prefrontal cortex.In group ME, 1 μmol/L endothelin + 1 μmol/L melatonin 0.5 μl was injected into the prefrontal cortex.In group L + ME, 1 μmol/L endothelin + 1 μmol/L MT 1/2R antagonist + 1 μmol/L melatonin 0.5 μl was injected into the prefrontal cortex.In group P + ME, 1 μmol/L endothelin + 1 μmol/L MT 2R antagonist + 1 μmol/L melatonin 0.5 μl was injected into the prefrontal cortex.T-maze and the open field tests were performed at 1 week after administration. Results:Experiment Ⅰ There was no significant difference in the locomotor speed in open field test among C, M and ME groups ( P>0.05). The rate of correct selection in T-maze test was significantly lower in M and ME groups than in group C and higher in group ME than in group M( P<0.05). Experiment Ⅱ There was no significant difference in the locomotor speed in open field test among the four groups( P>0.05). Compared with group M, the rate of correct selection in open field test was significantly increased in ME and P+ ME groups ( P<0.05), and no significant change was found in group L+ ME ( P>0.05). Compared with group ME, the rate of correct selection in open field test was significantly decreased in group L+ ME ( P<0.05), and no significant change was found in group P+ ME( P>0.05). Conclusion:Melatonin can attenuate prefrontal cortex ischemia-induced cognitive impairment in the rats, and the mechanism is related to activation of MT 1R.