The Action of Irradiated Ergosterol on Rats and Chickens

Abstract

It is generally taken for granted that there is a parallelism between rickets, the percentage of ash in the bones, and the concentration of inorganic phosphorus in the blood, and furthermore that factors which prevent or cure rickets are associated with a tendency to increase the bone ash and the phosphorus in the blood. In connection with infantile rickets, attention has been drawn from time to time by one of us to the fact that this disorder may be accompanied by a high concentration of inorganic phosphorus in the blood. In the course of an extended investigation, we have found that this same phenomenon may hold true for rats. Furthermore, a striking difference in this respect has been noted between the action of irradiated ergosterol and cod liver oil, when inadequate amounts of the former preparation are given. In a series of curative experiments it was found repeatedly that the inorganic phosphorus could be raised to normal concentrations, to 6 mg. or more per 100 cc. of serum, and that nevertheless no evidences of healing resulted, as judged by the “line test”. Animals treated in this way had a low percentage of bone ash, about 30%, which is an amount indicative of rickets. These rats were about 4 weeks old, weighed approximately 50 gm. and had been fed the Steenbock rickets-producing ration plus 10 cc. of reconstituted dry milk. On the other hand, when cod liver oil was added to the diet, in amounts varying from 7 to 20 mg. daily, marked healing followed and the bone ash increased, but the concentration of inorganic phosphorus in the blood did not rise above 2 to 4 mg. per 100 cc.