[Bioavailability and bone toxicity of barium chloride by chronic administration in rats].

Knowing long term total parenteral nutrition (TPN) can bring 12 micrograms/kg/day as barium contamination, we investigated the barium ability to give the same bone toxicity as observed in patients' underlying TPN. A preliminary study carried out on 21 rats allowed us to calculate the bioavailability of barium chloride (50%) with doses fixed at 1 mg/kg for the intravenous route and 10 mg/kg for the oral route. As it is very difficult to feed rats parenterally for more than 30 days, we decided to give barium chloride orally. Twenty rats received 48 micrograms/kg/day barium chloride during 4 months. The barium plasma and bone levels were not statistically different between the control group and the tested group. The femurs and tibias were removed for analysis, carried out by different fixation and coloration techniques. No anomalies could be detected in the treated group concerning main bone parameters that are disturbed in patients' underlying TPN.