Structural changes of dorsal root ganglion neuron injured by acute mechanical pressure: an AFM observation

English Keywords:Spinal cord injury  Mechanical pressure  Cell culture  Neuron cells  Atomic force microscope

English Abstract:

  【Abstract】 Objectives: To investigate the spinal cord injury mechanism especially the nanoscale reaction of membrane skeleton protein in spinal cord injury under mechanical pressure by using the cultured dorsal root ganglion neuron cells in vitro and simulation of mechanical injury device. Methods: The primary culturing of dorsal root ganglion neuron cells from new born S-D rats wsa used, and the mechanical pressure on cultured cells wsa added by the multi-functional automatically mechanical pressure equipment(national patent of utility model, ZL 200820030390.7). The cells were divided to 4 groups, group A, B, C and D. The group A was tested as control group. The group B, C and D experienced 0.3mPa, 0.5mPa and 0.7mPa mechanical pressure for 10 min respectively. The cells were fixed by formaldehyde when cultured for 8 hours, the ultra structure of the cell membrane skeleton protein was observed by AFM(atom force microscope), with 6 different Petri dishes of cells for each group. The nanoscale reaction of membrane skeleton protein wsa observed, the corresponding data of the height of the membrane particle and roughness parameters as well as the AFM photos were acquired. Results: The cell membrane of the control group was smooth and not apparently rough. The 0.3mPa group showed the particle height of cell membrane increased apparently compared with the control group, the membrane surface seemed more rough, and the peak value of the histogram of the protein height on cell surface shifted rightly. The 0.5mPa group showed more severe changes than the 0.3mPa group. The 0.7mpa group showed the particle height of cell membrane protein decreased and became less rough, nevertheless, some porous channel occurred at the membrane. The statistical results of the peak value, the maximal value and the width of particle height value indicated that different mechanical pressure value produced different membrane roughness(P<0.01). Conclusions: Different mechanical pressures produce different membrane roughness as well as the membrane skeleton protein, which can supply basis for protection of injured cells.