Abstract: Objective To quantitatively analyze the temporal and spatial pattern of RhoA expression in injured spinal cord of
adult mice. Methods A spinal cord transection model was established in adult mice. At 1, 3, 7, 14, 28, 56 and 112 days after the
surgery, the spinal cords were dissected and cryosectioned for RhoA/NF200, RhoA/GFAP, RhoA/CNPase or RhoA/IBA1 double
fluorescent immunohistochemistry to visualize RhoA expressions in the neurons, astrocytes, oligodendrocytes and microglia.
The percentages as well as the immunostaining intensities of RhoA-positive cells in the parenchymal cells were quantitatively
analyzed. Results RhoA was weakly expressed in a few neurons and oligidendrocytes in normal spinal cord. After spinal cord
injury, the percentage of RhoA-positive cells and RhoA expression intensity in the spinal cord increased and peaked at 7 days
post injury (dpi) in neurons, oligodendrocytes and astrocytes, followed by a gradual decrease till reaching a low level at 112
dpi. In the microglia, both the RhoA-positive cells and RhoA expression intensity reached the maximum at 14 dpi and
maintained a high level till 112 dpi. Conclusion Traumatic spinal cord injury can upregulate RhoA expression in the neurons
as well as all the glial cells in the spinal cord. RhoA expression patterns vary with post-injury time, location and among
different parenchymal cells in the injured spinal cord.