Objective To evaluate the effects of TMS on the brain plasticity and functional outcome after cerebral infarction in rats. Methods Twenty-four male Sprague-Dawley rats were divided randomly into a model group and a TMS group. The rat models of focal cerebral infarction were established with unilateral middle cerebral artery (MCA) suture occlusion method. The rats of TMS group were given additional 4 weeks of TMS treatment commenced at!1 day after infarction (2 times per day, 30 pulses per time), while those in the control group were reared in their original living state. Synaptic substructure in the sensori-motor cortex area was assessed morphologically and quantitatively. Results When compared with the model group, the rats in the experimental group had a significant improvement in terms of their neural functions (P

Objective To study the effects of transcranial magnetic stimulation (TMS) on the expression of c-Fos and brain-derived neurotrophic factor (BDNF) of the cerebral cortex in rats with cerebral infarction. Methods Cerebral infarction models were established by using of left middle cerebral artery occlusion (MCAO) and randomly divided into a model group (n=40) and a TMS group (n=40), in additional, TMS treatment (2 times per day, 30 pulses per time) with frequency of 0.5 Hz and magnetic field intensity of 1.33 Tesla was carried out in TMS group after infarction. The expression of c-Fos and BDNF was measured at 1 d, 7 d, 14 d, 21 d and 28 d after infarction, respectively. Results The positive expression c-Fos and BDNF was detected in the cortex around the infarction areas, while the expression of c-Fos and BDNF was increased significantly in TMS group in comparison to those in model group at 7 d, 14 d, 21 d, 28 d (P

BACKGROUND: Microglial cells are prominently involved in certain neurologic diseases such as Parkinson disease and Alzeheimer disease. In vitro primary culture is commonly used in studies on the functions of microglia.However, these classical culture methods have some defects including complex procedures and low out-put.OBJECTIVE: To establish a simplified high-output primary culture of microglia.DESIGN: An explorative experiment with microglial cells as the single sample.SETTING: Department of Neurology, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology.MATERIALS: The study was finished at the Central Laboratory of Union Hospital from April to October 2004. Microglial cells were obtained from 10 newborn(one day) male Kunming mice that were selected.METHODS: The author' s culture method was based on McCarthy method, we developed a new culture method and made some improvements,including the increased cell density for primary culture and nutritional deprivation. The microlglial cells were isolated with low-concentration trypsin-EDTA(ethylene diamine tetraacetic acid) digestion and immunochemically labeled with MAC-1 antibody, so as to measure the output and purity of microglia.MAIN OUTCOME MEASURES: ① Morphologic features of microglial cells, observed with inverted microscope; ② Purity and activity of microglia cultured with these two methods, were measured immunohistochemically.RESULTS: For microglia cultured with McCarthy method, the culture cycle was 20 days and the output was 2 × l05 cells per flask with a purity of 95% -97%. The new method shortened the culture cycle to 15 days and the output reached 1 × 106 cells per flask with a purity of 96-98%. Cell purity and activity had no significant difference between these two culture methods.CONCLUSION: The new method has a similar purity and activity with classical method; however, it may simplify procedures, shorten cycle, and increase output, and therefore can be a useful method for studies on microglia function and for nerve repair.

BACKGROUND: Studies have shown that mild hypertension and hypothermia both offer cerebral protection against focal cerebral ischemia,and their possible synergistic effect may provide even better neuroprotective effects.OBJECTIVE: To investigate the mechanism of cerebral protection by induced hypertension combined with mild hypothermia against focal cerebral ischemia and reperfusion, through observation of the changes in the infarct volume and blood-brain barrier(BBB) in rats.DESIGN: A randomized controlled experimental study based on experimental animals.SETTING: The departments of neurology of two university hospitals and department of dermatology in a municipal hospital.MATERIALS: The study was carried out in the Laboratory of Department of Neurology, Union Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology and Laboratory of Department of Neurology, People' s Hospital of Wuhan University from March to July 2001. Sixty-four Wistar rats weighing 180 to 230 g were purchased from the Experimental Animal Center of People' s Hospital of Wuhan University.INTERVENTIONS: Sixty-four rats were randomly divided into control group, hypertension group, mild hypothermia group, and combined therapy group, each group consisting of 16 rats. Reperfusion was initiated after a 3-hour focal cerebral ischemia of the 16 rats, and at 2 hour during the ischemia, the rats in the hypertension and mild hypothermia group were treated with hypertension for 3 hours and mild hypothermia, respectively, and those in the combined therapy group received both treatment. The rats in the control group received no treatments for ischemia and reperfusion. Twenty-four hours later, all rats were killed for examination.MAIN OUTCOME MEASURES: The scores of neurological deficits, infarct volume and degree of BBB damage.RESULTS: The scores for neurological deficits, infarct size and volume of Even' s blue staining were 2. 12 ±0. 54, (17.65 ±4.78)%, and(56.63± 10.70) mm3, respectively, in hypertension group, and 2. 14 ±0.69,(16. 21 ± 3.79)%, and(53.52 ± 8.44) mm3 in mild hypothermia group,and 1.78 ±0. 61, (11, 31 ±3.64)%, and 38.45 ±5.25 mm3 in combined therapy group, which were all decreased significantly as compared with the control group[2.70 ±0. 64, (28.34 ±4. 13)%, and(94.87 ± 15.34) mm3].The combined therapy group had the smallest infarct size and volume of Even's blue staining among the three treatment groups( P ＜ 0.05).CONCLUSION: Hypertension and mild hypothermia may reduce the infarct volume and alleviate BBB damage during focal cerebral ischemia and reperfusion in rats, and the effects of combined treatment are more obvious.

To explore the relationship between beta-amyloid (A beta) and the pathogenesis of Alzheimer disease (AD), after injection of beta-amyloid into the rat brain, the apoptosis of nerve cells and acetylcholine (Ach) content in rat hippocampus were examined by employing TUNEL technique and base hydroxylamine colorimetry respectively. The influence of age and glucocorticoid on the neurotoxic effect of A beta was also analyzed. A beta peptide could strongly induce the apoptosis of neurons in hippocampus, cortex and striate body (P < 0.05 or P < 0.01). In addition, the senility and glucocorticoid pre-treatment could enhance the toxic effect of A beta (P < 0.05 or P < 0.01). It is concluded that A beta may play an important role in the pathogenesis of Alzheimer disease via its induction of apoptosis of neurons and by decreasing the content of the Ach.
Acetylcholine/metabolism ; Aging ; Alzheimer Disease/etiology ; Amyloid beta-Protein/*toxicity ; Apoptosis/*drug effects ; Dexamethasone/*pharmacology ; Drug Synergism ; Hippocampus/metabolism ; Hippocampus/*pathology ; Injections, Intraventricular ; Neurons/pathology ; Rats, Wistar

Objective To study the effects of transcranial magnetic stimulation (TMS) on learning and memory, and angiogenesis and the dendritic structure of hippocampal CA3 pyramidal neurons after cerebral infarction. Methods Forty-eight male Sprague-Dawley rats were divided into a sham operated group, a model group and a TMS group (n = 16). Rat models of focal cerebral infarction were established with unilateral middle cerebral artery (MCA) suture occlusion in the model and TMS groups. The rats of the TMS group were given 4 weeks of TMS treatment beginning 1 day after the infarction (2 times per day, 30 pulses per time). Their learning and memory abilities were tested with a Y-maze. Angiogenesis and the dendritic structure of their hippocampal CA3 pyramidal neurons were detected after 4 weeks. Results Compared with the model group, learning and memory improved significantly in the TMS group. The average microvessel density of the hippocampus in the TMS group was significantly more than in the model group. The total length of apical dendrites of hippocampal CA3 pyramidal neurons in TMS group was significantly longer than in the model group. Conclusions The improved learning and memory observed following TMS treatment are likely to be related to changes in angiogenesis, the dendritic.structure of the hippocampal CA3 pyramidal neurons, and enhanced synaptic plasticity.

Objective To study the effects of NRG2 on cardiac structure and function , we established the cardiac-specific human NRG2 transgenic mice and investigate the effect of NRG2 on cardiac structure and function under pressure overload situation .Methods The transgenic vector was constructed by insertion of the human NRG2 gene under the α-MHC promoter.The transgenic mice were generated by microinjection and were all maintained on a C57BL/6J genetic background .The genotype of transgenic mice was identified by PCR and the expression level of target gene was determined by western blot .Transverse aortic constriction ( TAC) was applied to prepare the pressure overload induced cardiomyopathy mice model .The cardiac structure and function of the transgenic mice were compared and analysized by echocardiographic and pathological observation .Results Transgenic mice with high level of NRG2 in heart tissues were established.The left ventricular wall thickness (LVPWD) was increased, and to 15.6% at 3 months old compared with that of the non transgenic ( NTG) mice.The hypertrophy of left ventricular wall caused by pressure overload was removed due to the expression of NRG2 .Meanwhile, cardiac disarray and fibrosis were increased obviously compared with that of the NTG mice.Conclusion The transgenic expression of NRG2 in heart tissues could shorten the pathological process of hypertrophy, but accelerated the process of heart failure (HF).

Regulation of the adhesion molecules expression by cytokine in vascular endothelial cells was investigated. Human umbilical vein endothelial cells (HUVEC) were stimulated with cytokines, TNF-α (1-250 U/ml) or IL-1β (0.1-50 U/ml) for 24 h. HUVEC were also cultured with cytokines, TNF-α (100 U/ml) or IL-1β (10 U/ml), for 4-72 h, cell surface expression of adhesion molecules (ICAM-1 and VCAM-1) were detected and quantitated by immunocytochemical methods and computerized imaging analysis technique. Adhesion molecules expression were up-regulated by TNF-α, IL-1β in a concentration- and time-dependent manner. Some significant differences were observed between the effects of cytokines on the ICAM-1 and on VCAM-1 expression. Cytokines might directly induce the expression of ICAM-1 and VCAM-1 in vascular endothelial cells. Our observations indicate differential functions of the two adhesion molecules during the evolution of inflammatory responses in stroke.

Regulation of the adhesion molecules expression by cytokine in vascular endothelial cells was investigated. Human umbilical vein endothelial cells (HUVEC) were stimulated with cytokines, TNF-α (1-250 U/ml) or IL-1β (0.1-50 U/ml) for 24 h. HUVEC were also cultured with cytokines, TNF-α (100 U/ml) or IL-1β (10 U/ml), for 4-72 h, cell surface expression of adhesion molecules (ICAM-1 and VCAM-1) were detected and quantitated by immunocytochemical methods and computerized imaging analysis technique. Adhesion molecules expression were up-regulated by TNF-α, IL-1β in a concentration- and time-dependent manner. Some significant differences were observed between the effects of cytokines on the ICAM-1 and on VCAM-1 expression. Cytokines might directly induce the expression of ICAM-1 and VCAM-1 in vascular endothelial cells. Our observations indicate differential functions of the two adhesion molecules during the evolution of inflammatory responses in stroke.

To explore the relationship between beta-amyloid (A beta) and the pathogenesis of Alzheimer disease (AD), after injection of beta-amyloid into the rat brain, the apoptosis of nerve cells and acetylcholine (Ach) content in rat hippocampus were examined by employing TUNEL technique and base hydroxylamine colorimetry respectively. The influence of age and glucocorticoid on the neurotoxic effect of A beta was also analyzed. A beta peptide could strongly induce the apoptosis of neurons in hippocampus, cortex and striate body (P < 0.05 or P < 0.01). In addition, the senility and glucocorticoid pre-treatment could enhance the toxic effect of A beta (P < 0.05 or P < 0.01). It is concluded that A beta may play an important role in the pathogenesis of Alzheimer disease via its induction of apoptosis of neurons and by decreasing the content of the Ach.
Acetylcholine ; metabolism ; Aging ; Alzheimer Disease ; etiology ; Amyloid beta-Peptides ; toxicity ; Animals ; Apoptosis ; drug effects ; Dexamethasone ; pharmacology ; Drug Synergism ; Hippocampus ; metabolism ; pathology ; Injections, Intraventricular ; Male ; Neurons ; pathology ; Rats ; Rats, Wistar