Über experimentelle Beeinflussung der Leberfunktionen und der anatomischen Leberstruktur durch Einwirkung seltener Erden

The Behavior of Certain Lanthanons in Rats

“…The present experimental results confirm some earlier reports which state that the rare earth metals in a certain concentration are capable of lowering the level of glucose in the blood (Fischler & Roeckl 1938, Trapmann 1959, Snyder & Stephens 1961. Fischler & Roeckl (1938) made their observations on rabbits with lanthanum, neodymium, praseodymium, yttrium, and cerit, which is a mixtwe of various lanthanons but mainly cerium, neodymium, and lanthanum. Snyder & Stephens (1961) observed the blood sugar lowering effect after intravenous administration of cerium to rats.…”

“…Thus, according to this discussion, the acute liver damage produced by the rare earth metals ought to be responsible for the insufficient glycogen formation in the liver, which, in its turn, should cause hypoglycemia. This confirms the work of Fischler & Roeckl (1938) who correlated liver glycogen reduction and liver lanthanon concentration. It should also be kept in mind that a decreased appetite due to the intoxication plays a role in causing hypoglycemia.…”

“…After the intravenous administration of cerium to female rats, the liver shows a diffuse lesion in the form of a fatty degeneration. In this respect, the investigation confirms the earlier known fact that certain lanthanons (lanthanum to samarium) produce fatty liver degeneration in female rats (Fischler & Roeckl 1938, Hara & Sat0 1955, Kyker et al 1957a, Neubert & Hoffmeister 1960, 1960a, Snyder & Stephens 1961. In male rats, however, another picture was seen.…”

“…Furthermore, the lanthanons are not taken up to any great extent by the pancreas after intravenous administration (Ewaldsson & Magnusson 1963. The proposal that removal of liver degeneration products should stimulate the pancreas to increased insulin production is considered to be without foundation (Fischler & Roeckl 1938). Thus, it may be considered as highly unlikely that the hypoglycemia produced by the lanthanons is due to a disturbance in the pancreatic endocrine function.…”

“…Instead, the explanation of hypoglycemia should be sought in the liver with its key position in glucose metabolism. Fischler & Roeckl (1938) thought the cause of hypoglycemia to be an inactivation of liver enzymes and suggested the designation "Hypoglykamie durch Leberfermentlahmung". It is known that liver glycogen plays an important role in the regulation of the glucose level of the blood.…”