The humoral transport of beryllium.

Abstract

The mode of transport of Be in body fluids was investigated by ultracentrifugal, dialysis, and immunological techniques. Serum specimens were incubated with either Be oxide or Be sulfate at physiologic pH and temperature. In an in vitro study, a buffered 20% aqueous glycerol solution served as a protein-free control medium. The immunological study, evaluated by the allergic and anaphylactoid reaction as well as by the precipitin reaction, failed to show the development of antigenic property by the Beincubated serum. The results were consistent with the assumption that no significant extracellular Be-protein interaction takes place in vivo. Dialysis also demonstrated that presence or absence of protein in the medium has no effect on the diffusion rate of added Be at a concentration of 10/sup -4/ mole/l. Ultracentrifugal experiments, in addition to corroborating the results, also showed that the added Be is separable into at least 2 distinct fractions. Both possessed well-defined migration rates in the ultracentrifugal field, indicating that ionic Be in excess of 0.01 mu M/ ml was no longer present. A form having a density greater than 1.06 appeared to be the orthophosphate. Another form, having a density of about 1.04, seemed to be the hydroxide. For the humoralmore » transport of Be, it is proposed that if soluble Be enters by any parenteral route, immediate precipitation of Be orthophosphate takes place in situ. A minor portion of Be (2 to 3% at concent rations up to 10/sup -3/M) is precipitated as the hydroxide; the amount increases sharply when plasma Be attains a concentration high enough to exhaust all plasma phosphate. This precipitate is very light (density about 1.04) and more soluble than the orthophosphate. The colloidal precipitates are in dynamic equilibrium with any noncolloidal deposit formed in situ, as well as with traces of the ionic portion; the biological half life of the element in an organ is dependent on the relative amounts of the 3 forms. (TCO)« less