Balance and Tissue Distribution of Vanadium after Short-Term Ingestion of Vanadate

Abstract

Forty-six female Sprague-Dawley rats (170-200 g) were randomly assigned to one of six treatment groups receiving 0.1, 5.0, or 25.0 ppm dietary vanadium with either normal (0.13 mEq/g) or high (1.82 mEq/g) dietary potassium. Supplemental vanadium was administered as sodium metavanadate. These diets were fed for 2 weeks, and all feces and urine collected. At the end of the treatment period, brain, liver, renal cortex and medulla, whole blood, and plasma were obtained and analyzed for vanadium by atomic absorption spectrophotometry, as were the urine and feces samples. Tissue vanadium concentration increased significantly (P less than 0.00001) with increasing food vanadium content, but were not affected by dietary potassium in spite of the polyuria induced in animals on the high potassium diets. The highest vanadium concentrations were found in the renal cortex and the lowest, in the brain. Although urinary vanadium excretion was higher in animals fed the high potassium diets, a relatively small percentage of ingested vanadium was excreted in the urine. Rats fed diets containing no supplemental sodium metavanadate (0.1 ppm vanadium) were in negative vanadium balance, but their growth was not inhibited. Animals receiving 5.0 and 25.0 ppm vanadium diets retained 39.7 +/- 18.5% of ingested vanadium and excreted 59.1 +/- 18.8% of ingested vanadium in the feces. These values indicate greater absorption and retention of ingested vanadium than found In previously reported investigations.

Vanadium in diabetes: 100 years from Phase 0 to Phase I

“…The carrier-added, direct comparison study between 48 V-BMOV and 48 VOSO 4 [104] demonstrated a similar pattern of biodistribution to that of inorganic vanadium salts observed earlier [33,97,98,[139][140][141], especially with regard to the order of relative accumulation, with bone > kidney > liver. A long half-life of elimination (>10 d for 48 V in bone after a one-time 10 lM dose by oral gavage in rats) and low level of absorption (with bone retaining $0.1% of an oral dose/g tissue 24 h after an oral dose of VOSO 4 ), were corroborated for VOSO 4 in the carrier added study [104], and shown to be enhanced by BMOV, which had a two-fold longer half-life of elimination from bone.…”

“…2 for current rendition) [14]. Pharmacokinetic analyses predicted that most of an inorganic vanadium dose would be excreted rapidly, having never been absorbed at all [96][97][98]. Thus, an apparent overlap between toxic and therapeutic doses disappeared.…”

Vanadium

“…In rats, the renal cortex accumulated the highest, and the brain the lowest concentrations of vanadium (Bogden et al 1982). In goats with high (2000 mg Vkg À1 ) and low (< 20 mg V kg À1 ) vanadium contents in the feed DM, all organs analyzed reflected the different vanadium intakes significantly.…”

Opinion of the Scientific Panel on Dietetic products, nutrition and allergies [NDA] related to the Tolerable Upper Intake Level of Vanadium

“…Uptake of radioactive vanadium pentoxide (V 2 O 5 ) given orally to rats was 2.6% of the administered dose (Conklin et al, 1982). Other studies in rats have indicated that amounts greater than 10% can be absorbed from the gastrointestinal tract under some conditions (Bogden et al, 1982;Wiegmann et al, 1982).…”