The Experimental Production of Loss of Hematopoietic Elements of the Gastric Secretion and of the Liver in Swine with Achlorhydria and Anemia.

The mode of origin of pernicious anemia and of conditions symptomatically allied to it, sprue and tropical macrocytic anemia, has been the subject of detailed and extensive investigation during the last decade. Although considerable advances have resulted from clinical studies in spite of limited material, one of the chief handicaps to more rapid progress has been the difficulty of reproducing similar diseases in animals. Certain isolated pathological changes including glossitis, macrocytic anemia and achlorhydria, similar to those of pernicious anemia, have been caused to occur independently, but in no reported instance have the major pathological and physiological alterations of pernicious and allied anemias been produced as a disease syndrome in a lower animal species. The present communication deals with the results of an attempt to cause in swine a symptom-complex which might be etiologically, symptomatically , therapeutically and pathologically similar to that characterizing the group of macrocytic anemias of man. The condition studied was brought about by the administration of a specially devised diet, and was marked by hematological, lingual and gastro-intestinal changes similar to, though not entirely identical with, those of pernicious anemia and of conditions allied to it. To comprehend thoroughly the rationale of the experiments to be reported, a brief review is required of the conditions in human beings which it was desired to simulate. Pernicious anemia, the anemia of sprue, and tropical macrocytic anemia, present hematological changes which are, in a general way, similar. A further likeness lies in the fact that all three may be alleviated by the administration of whole liver or of a suitably prepared extract. Distinct differences exist, however, among which are the dissimilar effects following the administration of a lysate of brewers' yeast. Whereas the symptoms of tropical macrocytic anemia are regularly alleviated by the administration of that material, favorable results are only occasionally obtained in sprue and in pernicious anemia. If, in the latter two conditions, however, the administration of the yeast extract is supplemented by the administration of normal gastric secretion, which, by itself , is inactive, the combination is therapeutically active (Strauss and Castle (6)). The most plausible explanation of the foregoing facts is that all three symptom-complexes are due to the same fundamental cause-a lack of some substance such as that contained in the yeast cell. Such a lack may be a simple dietary insufficiency, as in the case of tropical macrocytic anemia, or it may be …