Androgen regulated expression of the alpha 2u-globulin gene in pancreatic hepatocytes of rat.

Abstract

Abstract. Under a copper-deficient regimen, pancreatic cells in the adult rat can be found to undergo differentiation into hepatocytes. Pancreatic hepatocytes induced in male and female rats were examined for the expression of the androgen-inducible hepatic protein, o~-globulin. C~2u-Globulin protein was demonstrable by immunoperoxidase method in all the pancreatic hepatocytes of male rats. Northern blot analysis confirmed the presence of 1.3 kb ot2u-globulin mRNA transcript in the pancreas of male rats with hepatocytes. Orchiectomy resulted in marked decrease of c~2~-globulin protein and its mRNA. Administration of dihydrotestosterone to castrated rats resulted in increased levels of or:uglobulin mRNA and the amount of c~2u-globulin protein in the pancreatic hepatocytes. Unlike normal males, in intact and ovariectomized females t~2u-globulin was not detectable in pancreatic hepatocytes. These results indicate that similar to hepatic parenchymal cells pancreatic hepatoeytes synthesize t~2~-globulin under androgenic regulation. Furthermore, unlike in liver where it is expressed predominantly in perivenular and midlobular hepatocytes, there is no localized difference in the expression of this gene in the transdifferentiated pancreatic hepatocytes.

Functional Hepatocellular Heterogeneity for the Production of Plasma Proteins

“…tivity of these receptors in the hepatic lobule have not yet been achieved. Activation of hepatocyte receptors by growth factors or mediators secreted locally by sinusoidal cells is another possibility [73] which could be supported by the following observation: the formation of hepatocytes in the pancreas can be induced by a chronic copper-deficient regimen [89]. The ectopic hepatic tissue loses its lobular organization and particu larly its sinusoidal vascularization and sinu soidal cells.…”

An expandable donor-free supply of functional hepatocytes for toxicology

“…Dioxin (2,3,7,8-tetrachlorodibenzop-dioxin, TCDD) treatment 100 Hamster Two or 6 intraperitoneal injections of 100 μg per kg bw at 4 week intervals induced pancreatic hepatocytes in 75% and 89% of the animals respectively. Copper depletion/repletion 101 Rat Pancreatic hepatocytes appear in both male and female pancreata in this model. Male pancreatic hepatocytes synthesize in all cells, the male liver (centrilobular-specific) alpha 2u-globulin Aunder androgenic regulation.…”