Zinkgehalt und blutzuckersteigernde Wirkung von Organextrakten

Abstract

Crystalline preparations of insulin have a primary hyperglycemic effect. There was a correlation between this effect and the Zn content and it was possible to separate the insulin preparations into fractions causing only a lowering of the blood sugar, and a fraction causing the hyper-glycemic effect which contained all the Zn. It was now shown that fetal calf pancreas, which is particularly rich in Zn, also yielded extracts with a much higher hyperglycemic activity than could be obtained from the pancreas of adult animals. From crude insulin, with a high Zn and glucagon content, insulin with a very low Zn content could be crystallized, leaving the bulk of the Zn in the mother liquor where also the glucagon activity remained behind. No hyperglycemic factor could be isolated from the prostate of the dog, which is also rich in Zn. Human intes-tinal carcinoids have a high Zn content of the same order as the islet tissue of pancreas. It was not possible to make extracts of these carcinoids (not sufficient were available for study). It is known that these carcinoids have a high serotonin content, but serotonin had no hyperglycemic effect.