Effect of endogenous brain derived neurotrophic factor on GAP-43 expression in the anterior horn of the spinal cord in rats with sciatic nerve injury / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of endogenous brain derived neurotrophic factor (BDNF) on GAP-43 expression in the anterior horn of the spinal cord in rats following sciatic nerve injury.</p><p><b>METHODS</b>BDNF antibody was injected intraperitoneally in rats with crushing injury of the sciatic nerve, and the control rats received normal saline only after sciatic nerve injury. At 7 and 14 days after the injection, the expression of GAP-43 in the anterior horn of the corresponding segments of the spinal cord was detected by Western blot and RT-PCR.</p><p><b>RESULTS</b>The expressions of GAP-43 protein and mRNA in the anterior horn of the spinal cord were significantly down-regulated in rats with BDNF antibody injection as compared with those in the control group (P<0.01).</p><p><b>CONCLUSION</b>Endogenous BDNF may regulate the expression of GAP-43 in the spinal cord anterior horn after sciatic nerve injury in rats.</p>

The effects of exercise-induced fatigue on acetylcholinesterase expression and activity at rat neuromuscular junctions.

Acetylcholinesterase is the enzyme that terminates neurotransmission by hydrolyzing the acetylcholine released by the motoneurons at the neuromuscular junctions. Although acetylcholinesterase has been studied for almost a century, the underlying relationship between exercise-induced fatigue and acetylcholinesterase activity at the synaptic cleft is not clear. The purpose of this study was to assess the effects of exercise-induced fatigue on the expression and activity of acetylcholinesterase at the neuromuscular junctions. The expression and activity of acetylcholinesterase at the gastrocnemius neuromuscular junctions was decreased transiently by exercise-induced fatigue and then gradually increased over 24 hr. The expression of acetylcholinesterase in the 24 hr recovery group returned to the level of the control (non-exercised) group, but the activity of acetylcholinesterase remained significantly lower. These data suggest that the decrease of acetylcholinesterase expression and activity may be involved in the production and/or maintenance of exercise-induced fatigue.

Differential proteomic analysis of nasal polyps, chronic sinusitis, and normal nasal mucosa tissues.

OBJECTIVE: To compare protein expression in nasal polyps, chronic sinusitis, and normal nasal mucosa tissues using proteomic technology. DESIGN: Cross-sectional survey. SUBJECTS AND METHODS: Proteins extracted from the three kinds of tissues (seven samples per group) were separated by immobilized pH4-7 gradient two-dimensional gel electrophoresis (2-DE). PDQuest software was used to analyze 2-DE images, and the differentially expressed protein spots were identified with the use of both MALDI-TOF-MS and ESI-Q-TOF-MS. Of the differentially expressed proteins, Cu/ZnSOD and PLUNC were validated with the use of immunohistochemical tests. RESULTS: High-resolution, reproducible 2-DE patterns were obtained, and 30 differentially expressed protein spots were found. The intensity of Cu/ZnSOD and PLUNC differed significantly on immunohistochemical validation. CONCLUSION: These differentially expressed proteins are involved in airway inflammatory reaction, immune response, oxidative stress, and metabolic reaction after exposure to irritants. In the future, several of these proteins may prove useful for exploring the pathogenesis of nasal polyps and chronic sinusitis or as objective biomarkers for quantitatively monitoring disease progression or response to therapy.

Dopamine D2 receptor and transportor corrected in the medial prefrontal contex of morphine-induced conditioned place preference in Sprague-Dawley rats / 中南大学学报(医学版)

OBJECTIVE@#To investigate the expression of dopamine D2 receptors (D2R) and dopamine transportors (DAT) located in the medial prefrontal contex (mPFC) in high and low conditioned place preference (CPP) rats, and to unveil the possible mechanism leading to different CPP susceptibilities.@*METHODS@#One hundred and sixty male Sprague-Dawley rats were randomly assigned into an experiment group (n = 130) and a control group (n = 30). The experiment group was re-classified into 2 groups according to CPP values:high preference group (HP group) and low preference group (LP group). According to the execution time-points after the last administration, the HP and LP group was classified into a 3-hour group (3 h), a 72-hour group (J3d), and a 14-day group (J14d), respectively. At 3 hours, 72 hours, and 14 days after the final injection, rats were killed and cardio-perfused, and the brains were removed and sliced up coronarily. The mRNA levels of D2R and DAT in mPFC were determined with in situ hybridization.@*RESULTS@#There were no significant differences of pretest scores staying at the non-preference chamber among the groups(P = 0.470). However, the test scores of the CPP time stayed at pretest natural preference in the HP group were significantly higher than those of the LP group(P = 0.000). In 3h, J3d, and J14d groups,the expressions of D2R mRNA in the HP group (125.43 +/- 2.90 approximately 142.92 +/- 3.32) were lower than those of LP group (122.25 +/- 2.20 approximately 136.67 +/-5.39) (P = 0.000). In 3h and J3d,the expressions of DAT mRNA in the HP group (157.00 +/- 3.55 approximately 145.15 +/- 3.69) were significantly lower than those of the LP group (150.69 +/- 3.12 approximately 138.84 +/- 3.99) (P = 0.000). In J14d, there were no differences among 3 groups in mPFC (P = 0.458).@*CONCLUSION@#D2R and DAT may be correlated closely and underlie the different susceptibilities to morphine induced CPP.

Expression of brain-derived neurotrophic factor in hippocampus of ovariectomized mouse / 中南大学学报(医学版)

OBJECTIVE@#To explore the expression of brain-derived neurotrophic factor (BDNF) in the hippocampus after ovariectomy in mice.@*METHODS@#BDNF levels were detected by immunohistochemistry combined image analysis in hippocampal CA regions and dentate gyrus of ovariectomized mice.@*RESULTS@#The expression of BDNF in hippocampus of mice decreased significantly after the ovariectomy after 4 days. The recovery BDNF expression started 14 days after the ovariectomy and after 28 days, the expression of BDNF in hippocampus recovered to the normal level.@*CONCLUSION@#The decrease of estrogen in ovariectomized mice can weaken the expression of BDNF in hippocampus during the early stage.