Accumulation and depletion of vanadium in selected tissues of rats treated with vanadyl sulfate and sodium orthovanadate.

Experiments were conducted to determine the distribution and effects of selected vanadium (V) salts in male rats following continuous ingestion. Wistar rats were continuously fed drinking water ad. Lib. containing 5 and 50 ppm V as vanadyl sulfate and sodium orthovanadate for a 3 month period. At the end of the 3rd, 6th, 9th, and 12th week, blood, kidney, liver, bone, muscle, and digestive tract were collected and analyzed for V utilizing flame atomic absorption spectrophotometry. In addition, the decline of vanadium residues in tissues after 6 weeks of continuous exposure was studied in selected groups. At the 5 and 50 ppm levels, V had no significant effect on body weights or hematocrit values. In the tissues of animals given 5 ppm of V salt, the V contents were essentially the same as those in controls. The tissues of animals given 50 ppm of V salt showed increased levels of vanadium. Kidney had the highest concentration, followed by bone, liver, and muscle. In general, the tissue concentrations of V in animals given 50 ppm as sodium orthovanadate were higher than those exposed to similar levels as vanadyl sulfate. The V concentration in kidney of the animals given 50 ppm sodium orthovanadate continued to rise until the 9th week of sampling, whereas the V content of other tissues analyzed for the treated animals plateaued from the 3rd week. The concentration of V in tissues after cessation of exposure declined rapidly except in the bone. After 6 weeks of the depletion phase the concentration of vanadium in animals given vanadyl sulfate returned to control values except in bone and kidneys. The animals exposed to sodium orthovanadate contained relatively high concentrations of V even after a 6 week depletion phase.