Fig. 6. Immunohistochemical staining of spinal cord for inducible nitric oxide synthase (iNOS) (magnification ×40) and histogram of average intensity of iNOS expression in ventral gray matter. (  A ) A representative picture of the Control group. Positive staining for iNOS is  green. Note that iNOS expression was found in proliferated glia cells (  arrow ) and that motor neurons were obviously swollen without iNOS expression (  asterisk ). (  B ) A representative picture of the Cooling group. Positive staining for iNOS is  green. Note that iNOS was expressed in motor neurons (  asterisk ), which have normal architecture, and that no proliferation of glia cells was found. (  C ) Histogram of average intensity of iNOS expression in ventral gray matter of spinal cord. Average intensity in the Cooling group was significantly augmented  versus the Control group (  P = 0.01275).