Note on the Metabolism of Copper in Splenectomized Rabbits

Abstract

In previous studies 1 it was found that removal of the spleen in albino rats free from Bartonella muris infection is followed by an increased elimination of copper, which produces a negative copper balance. In a study of the metabolism of rabbits before and after splenectomy we found that removal of the spleen causes an increase in copper excretion in this species as well.

Two rabbits were splenectomized at the age of 2 ½ months, after a foreperiod of 3 weeks, while another one was kept as a control under identical conditions. They were given alfalfa hay, oats and copper-free water, which was also used for all chemical determinations and for washing everything that came in contact with the animals. Urine was collected daily, feces twice a week. The urine was analyzed for total nitrogen (Kjeldahl), total sulphur (Benedict), total and inorganic sulphates (Folin), calcium (volumetric), phosphorus (Fiske-Subbarow), and copper. 2 Feces, hay and oats were analyzed for total nitrogen, calcium, phosphorus, copper and iron. 3

Our experiments show that splenectomy causes no change in the metabolism of nitrogen, sulphur, phosphorus and iron in rabbits. The calcium excretion proceeds unchanged after splenectomy, which also tends to show that the spleen is not involved in the regulation of calcium metabolism.

While the excretion of copper in the intact animal was remarkably constant, it increased in the splenectomized animals a week after the operation. The increase takes place in the feces, since the greater part of copper is excreted by the gut. The excretion of copper by the kidney does not seem to be influenced by splenectomy, though a larger amount of the total copper excreted is found in the urine in rabbits than in rats. As shown in the table, the copper intake on a diet of hay and oats is insufficient to maintain a positive copper balance in a growing rabbit, but the loss of copper from the body increases considerably after splenectomy.