Reduction of dietary phosphorus absorption by oral phoshorus binders

The aim of this study was to study a possible new non-aluminum phosphate-binder to limit hyperphosphatemia in patients with renal failure. Zirconyl chloride octahydrate was evaluated as a dietary phosphate binder in rats. Aluminum chloride hexahydrate was used as a reference. Animals were divided into six groups (6 animals per group): One - control group (C), two - aluminum groups (Al1 and Al2) and three - zirconium groups (Zr1, Zr2 and Zr3) receiving different doses of zirconyl chloride octahydrate. Urines were collected during the experimental period. At the end of the treatment, the animals were sacrified and plasma and different organs were collected (liver, spleen, kidneys, brain and femur). Determination of phosphorus and calcium levels in plasma indicated that zirconyl chloride octahydrate yielded as good results as aluminum chloride hexahydrate did. Zirconyl chloride octahydrate significantly (p<0.01) reduced bone phosphorus burden. Urinary excretion of phosphorus indicated a severe phosphorus depletion in all treatments. Not even traces of zirconium could be determined in the different tissues, in urines or in plasma. Consequently, it is important to carry out experiments with zirconium compounds in order to develop non-aluminum-containing phosphate binders.