title: Demonstration of embryonic-type hemoglobin in extramedullary hematopoietic cells in the liver during experimental liver carcinogenesis by 3'-methyl-4-dimethylaminoazobenzene.
abstract: Using an immunofluorescent technique, we demonstrated the production of rat embryonic-type hemoglobin in extra-medullary hematopoietic cells, which appeared in the liver of adult Wistar rats fed a diet containing 0.06% 3'-methyl-4=dimethylaminoazobenzene. Specific anti-rat embryonic hemoglobin serum was prepared by immunizing a rabbit with hemoglobin from a 15- or 16-day-old Wistar rat fetus and absorbing with adult rat liver hemogenate and red blood cells. The appearance of hematopoietic foci was observed at both precancerous and cancerous stages during 3'-methyl-4-dimethylaminoazobenzene-induced liver carcinogenesis. At the cancerous stage, almost all these foci were observed in poorly differentiated hepatocellular carcinomas. The hematopoietic cells seen at both stages were stained positively with antiembryonic hemoglobin serum, but red blood cells and other types of cells in the liver did not show this specific fluorescence. These results together with earlier observations on the appearance of fetal characteristics strongly suggest that a fetal environment prevails in the adult rat liver during hepatic carcinogenesis.
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000378:metabolism; D006412:Hematopoietic Stem Cells / Q000378:metabolism*; D006446:Hemoglobin E / Q000096:biosynthesis*; D006455:Hemoglobins, Abnormal / Q000096:biosynthesis*; D008099:Liver / Q000378:metabolism*; D008114:Liver Neoplasms, Experimental / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008749:Methyldimethylaminoazobenzene; D051381:Rats
chemical_list: D006455:Hemoglobins, Abnormal; D008749:Methyldimethylaminoazobenzene; D006446:Hemoglobin E