Effect of reversed polarity microcurrent electrical stimulation on an experimentally induced Achilles tendon injury in male albino rats: a histological and immunohistochemical study

The application of electrical stimulation can lead to a greater and faster increase in the rate of wound healing, especially when applying the cathedral [negative] stimulation for the first week, followed by the anodal [positive] polarity for the rest of the treatment period. The present work aimed to study the effect of polarity reversal of microelectrical current stimulation [MES] on the healing process in an experimentally induced Achilles tendon injury in rats. Forty three male albino rats were used in this study; they were classified into group I [control group] and group II [experimentally injured group], which was further classified into subgroups, I, II, III and IV. Subgroup I represents the injured tendon without MES treatment, whereas subgroups II, III and IV represent the MES-treated ones. The obtained tendon sections were subjected to H and E staining. Masson's trichrome stain, and immunohistochemical staining for alpha smooth muscle actin [alpha SMA], followed by morphometric study and statistical analysis. Subgroup I showed signs of inflammation, a few thin irregularly arranged collagen, active fibroblasts that start to align in rows on the regenerating collagen bundles, and alpha SMA immunoreactivity. In anodal-treated tendons, signs of inflammation had started to disappear; collagen fibers appeared thin and irregularly arranged, active fibroblasts were obviously observed and minimal alpha SMA immunoreactivity were recorded only in subgroup II. Cathodal-treated tendons showed rapid disappearance of cellular infiltration; most collagen fibers appeared regularly arranged with mature fibrocytes in between and multiple avoid alpha SMA immunoreactive myofibroblasts were maximally observed in subgroup II. alpha SMA was suggested to play a role in wound healing due to its high immunoreactivity in myofibroblasts during wound healing. Moreover, the application of electrical stimulation by applying cathodal [negative] stimulation for the first week, followed by anodal [positive] polarity for the rest of the treatment period may lead to better repaired tissue due to myofibroblast directional attraction to the cathode, especially when applied for 4-week duration

Electron microscopic study of nasal secretory glands and epithelium in perennial rhinitis

The morphology of nasal secretory glands and epithelium was studied using the electron microscope in ten patients with perennial rhinitis. Marked predominance of the serous type over mucous acini was the most conspicious feature. The cells were full of zymogen granules. Thickening and hyperplasia of the epithelium with marked ciliary loss was notified