A “Lipoid” Extract of Spleen that Prevents Baitonella Muris Anemia in Splenectomized Albino Rats

Abstract

The authors 1 have demonstrated that minute splenic autoplastic transplants made 7 weeks prior to splenectomy protect a large percentage of splenectomized rats from Bartonella muris anemia. A comparative histological study of the transplants of protected and unprotected rats revealed a regeneration of the pulp cells in the protected rats and an exhaustion destruction of the pulp in the unprotected rats. This supported the hypothesis that the reticular and endothelial cells of the pulp of the spleen possess some internal secretory substance. The parabiotic experiments of Lauda 2 further support the internal secretory action of the spleen. He found that rats joined by parabiosis are protected if the spleen of only one animal is removed.

Many investigators have tried and failed to demonstrate some substance in the spleen which would replace the spleen in protecting adult splenectomized rats against Bartonella muris anemia. We have made many attempts during the past three years to obtain such an extract. Lipoid extracts of the spleen were prepared which possess the property of protecting splenectomized adult albino rats against Bartonella muris anemia in a large percentage of instances. Since the anemia in the male is more severe, only male rats were used in testing these extracts. Of 440 male rats of carrier stock used for studies of Bartonella muris anemia during the past 3 years, not a single rat failed to develop Bartonella muris anemia following splenectomy.

Preparation of the extract. The spleen extract was prepared in a manner similar to Hartman's method of extraction of the suprarenal cortical hormone. Ox spleen freshly obtained from the slaughter house is repeatedly extracted with peroxide-free ether in the dark in an atmosphere of CO₂. The ether extractions are evaporated in vacuo at 15-20°.