Experimental Fetal Nephritis

Abstract

The problem of uranium poisoning in the pregnant animal has been investigated by MacNider, Helms, and Helms, 1 who found that during gestation susceptibility to this poison is especially marked, and that the changes in the blood, urine, liver, and kidneys, as well as the clinical course, resemble certain major toxemias of pregnancy in man.

Our interest in this problem has been to determine whether the fetus likewise suffers from the intoxication. The series studied at Beirut comprised 4 dogs, 10 rabbits, one normal pregnant dog and one normal pregnant rabbit for control. More recently observations have been made on 2 dogs, 6 rabbits, and one cat. The results with the latter group are essentially the same as those in the first group, the data for which are outlined in Tables I and II. Uranium acetate was used in our experiment. MacNider and his associates employed uranium nitrate.

Regarding the effect on the pregnant animal, our results confirm those of MacNider, Helms, and Helms, who employed injections of 4 mg. of uranium nitrate per kg. We used smaller doses in most of our experiments in an attempt to obtain living offspring and found that 1 mg. per kg. in the case of dogs was sufficient to produce a very marked intoxication.

A brief statement of the microscopic findings is given in Table II. The changes in the glomeruli were found to be somewhat variable, both in the mother and young, but greater uniformity was noted in the case of the tubules. Such variations as occurred could be explained on the basis of such factors as dosage, duration of the intoxication, and the opportunity for reparative processes. Marked dilatation of the convoluted tubules (Fig. 1), suggestive of cystic kidney, was a frequent occurrence in the new born, especially in the puppies. This was apparently due to obliteration of the collecting tubules, at least in part, from compression by proliferating connective tissue (Fig. 2).