ABSTRACT
This study was undertaken to determine whether colon cancer (CC) and chronic swimming exercise alter rat testis. Eleven weeks old rats were distributed into control group (n=6) and the groups that were induced to develop CC by dimethylhydrazine injections (nEG, EG0, EG2 and EG4; n=10 each group). In the group nEG, the rats did not swim, whereas groups EG0, EG2 and EG4, underwent a swimming program with distinct loads (0, 2 and 4% of body mass, respectively) for 35 weeks. The morphometry, stereology and cell counts showed damage caused by the CC on the germ epithelium. These results were noteworthy since this was the first report to associate the CC with testicular damage. Swimming exercise had no significant role in reducing, or increasing the CC effects on the testis, despite having slightly improved the testis structure of the exercised rats without load. In conclusion, CC caused testis impairment, which could not be avoided by the swimming exercise.
ABSTRACT
The elastic system fibers are abundant elements of the extracellular matrix found in organs such as skin, blood vessels, lung and in elastic cartilage and elastic tendons. These fibers have been studied by several selective staining methods, such as resorcin-fuchsin for light microscopy and hematoxylin-eosin plus fluorescence and confocal scanning laser microscopy. However, most of these techniques are only efficient for tissues embedded in paraffin or paraplast, since most dyes show low penetration into glycol methacrylate resins. In this report, we describe a variation of Weigert´s resorcin-fuchsin method that involves the pretreatment of resin sections with potassium permanganate. This procedure increased the affinity between the dye and elastic fibers, and stained the elastic fibers in black of dark violet, the nuclei in purple and other structures in light blue. Thus, this modification of the original method provided excellent artifact-free demarcation of elastic fibers in well-preserved tissues.