Abstract
A major development was the discovery that steel could be made highly resistant to corrosion and discoloration by adding metallic chromium to form stainless steel. This application along with chrome plating (electroplating with chromium) currently comprise 85% of the commercial use for the element. Trivalent chromium (Cr (III)) ion is possibly required in trace amount for sugar and lipid metabolism, although the issue remains in debate. In larger amounts and indifferent forms, chromium can be toxic and carcinogenic. The most prominent example of toxic chromium is hexavalent chromium (Cr V1). The present work was designed to evaluate the ameliorating role of vitamin c against the toxic and the possible carcinogenic effects of hexavalent chromium compound administered to male albino rats via drinking water for 3 months. Also to provide baseline information on the possible histopathological alterations developed in submandibular salivary glands. In this study 18 male albino rats (200- 220gm body weight) were utilized. They were divided into three groups, 6 animals each. The first group was considered control group and received drinking tap water for 3months. The second group was the experimental group and received drinking tap water containing 300ug/L of Cr (VI) as chromium trioxide for 3months. The third group, received drinking tap water containing 300ug/L of Cr (VI) as group II. In addition the animals of group III were injected intramuscularly by 10mg/kg body weight of vitamin C, twice weekly for the whole duration of the experiment. Samples from the submandibular salivary glands were fixed in 10% buffered neutral formal in and prepared routinely for paraffin sectioning and staining for histological and immune his to chemically immune expression of proliferating cell nuclear antigen (PCNA). Group II animals revealed marked histopathological degenerative changes in submandibular salivary glands. The striated duct appeared dilated, while granular duct showed stagnant eosinophilic secretion. The nuclei of the acinar cells showed hyperchromatic and abnormal mitosis. The acinar cells presented granular cytoplasm, while others showed empty vacuoles. The connective tissues stroma revealed increase in thickness. There was prominent inter- acinar edema. The blood vessels were congested and engorged with blood. The immune expression of PCNA in the nuclei of the acinar cells was intense after 3months daily administration of drinking tap water containing 300ug/L of Cr (VI). Group III received vitamin C in addition to Cr (VI), revealed some recovery to the normal structure of the submandibular salivary glands, and moderate immune reactivity to PCNA, which might revealed the protective antioxidant effect of vitamin C against cytotoxic effect of hexavalent chromium. The present study proved that the degenerative changes induced by hexavalent chromium in the submandibular salivary glands of male rats decreased in the group given vitamin C. The antioxidant effect of vitamin C was partly prevent the toxicity of hexavalent chromium.