Objective To explore the role of pregabalin on the expression of c-fos in spinal dorsal horn of the rat with neuropathic pain.Methods Thirty Wister rats (male) were divided into shamoperated group,model group and pregabalin group,with 10 cases in each group.The effect of the pregabalin on the heat pain threshold and expression of c-fos in spinal dorsal horn of the rat with neuropathic pain were observed.Results The heat pain threshold in model group at 3rd,4th,5th,6th,7th,10th and 14th day after operation was significantly lower than that in sham-operated group and pregabalin group at same time (P ＜ 0.05).The heat pain threshold in pregabalin group was lower than that in sham-operated group from 2nd day after operation,but there was no significant difference (P ＞0.05).At the 14th day after operation,the number of Fos-like-immunoreactivity (FLI) positive cells in sham-operated group,model group and pregabalin group was (16.4 ± 0.6),(66.7 ± 3.3) and (22.8 ± 1.5)cases,and the number of FLI positive cells in model group was significantly higher than that in shamoperated group and pregabalin group (P ＜ 0.05).Conclusions Pregabalin has analgesic activity on rat with neuropathic pain.Pregabalin activates spinal cord glial cells raisedby the injured peripheral nerve and infection,and also reduces the noxious stimulation of afferent pain to spinal dorsal horn neurons.

BACKGROUND: With the rapid development of tissue engineering, a single biological scaffold material is hard to meet the needs of tissue engineering. Therefore, composite scaffolds with excellent performance will be obtained by combining two or more kinds of materials.OBJECTIVE: To detect the adherence and proliferation of dental pulp stem cells on the Chitosan-fibrin composite scaffold.METHODS: Dental pulp stem cells were isolated and extracted from C57 neonatal rats through modified enzyme-digestion method, and subcultured to the third generation, followed by adipogenic and osteogenic induction in vitro. Then, induced cells were identified. The chitosan-fibrinogen composite scaffold was prepared, and the pore size and porosity were determined. The chitosan-fibrin composite scaffold was co-cultured with passage 3 dental pulp stem cells to observe the cell proliferation by MTT assay, and the morphology of the composite scaffold, cell adhesion,proliferation and extracellular matrix secretion were observed under scanning electron microscope. In addition, the cells were inoculated directly on the bottom of culture plate as controls.RESULTS AND CONCLUSION: The dental pulp stem cells were successfully isolated and cultivated, and positive for osteogenic and adipogenic differentiation. The pore size and porosity of the composite scaffold was (105.32±22.10) μm and (87.714±1.276)%, respectively. The S-shaped proliferation curve in the experimental group was similar with that in the control group; the proliferation rate in the experimental group was significantly higher than that in the control group after 4-8 days of culture (P < 0.05). At the 2nd day after co-culture, the cells adhered tightly and grew well onto the composite scaffold; at the 4th day, enlarged cells began to proliferate obviously with abundant extracellular matrix; the surface and pores of the scaffold were full of cells at the 6th day. These results indicate that the chitosan-fibrin composite scaffold is suitable for the adhesion and proliferation of dental pulp stem cells.