Histological appearances of mouse hind footpads after subcutaneously injecting 0.9% saline (Control group) or Carr, and then stained with H&E stain, while others were processed for iNOS and COX-2 immunohistochmistry staining.

<p>(A). Control mice: show the normal appearance of dermis and subdermis without any significant lesions, (F) iNOS and (J) COX-2 immunoreactive cells existed in the paws of normal mice; (B). Carr Only: Hemorrhage with moderately extravascular red blood cell and large amounts of inflammatory leucocytes, mainly neutrophils infiltrating the subdermis interstitial tissue. Moreover, the detail of the subdermis layer show enlargement of the interstitial space caused by the exudate fluid in the edema, (G) numerous iNOS and (K) COX-2 immunoreactive cells were observed in the brown site of paw tissue; (C). Carr + Indo 10 mg/kg (<i>i.p.</i>) (100×): there were obvious morphological alterations and improvements, (H) iNOS and (L) COX-2 immunoreactive cells; (D). Carr + inotilone: there were significant morphological alterations compared to the tissue with Carr treatment only. The lesions showed no hemorrhage and the number of neutrophils infiltrating the subdermis interstitial tissue was markedly reduced and also in (I) iNOS and (M) COX-2 immunoreactive cells in paws. Scale bar = 100 µm. There were markedly fewer inflammatory cells, and iNOS and COX-2 immunoreactive cells in the paws of Carr treated mice. The infiltrating cells were predominantly neutrophils (N; arrows). The brown staining indicated the interaction of primary and secondary antibodies and the presence of iNOS and COX-2.