Compared promoting potential of D-galactosamine, carbon tetrachloride and partial hepatectomy in rapid induction of preneoplastic liver lesions in the rat.

Effectiveness of two different chemically induced stimuli for hepatocellular proliferation was compared with regard to that of commonly used partial hepatectomy (PH), for the purpose of developing short-term protocol for the assay of promoting agents of hepatocarcinogenesis. Enhancing effect of D-galactosamine (DGA) and carbon tetrachloride (CCl4) given during the promotion procedure by 2-acetylaminofluorene (2-AAF) was compared along with PH in rats initiated by diethylnitrosamine (DEN), using preneoplastic glutathione S-transferase positive (GST-P+) hepatocyte foci as an end-point marker lesion. The number of GST-P+ foci per cm2 was largest in the group given CCl4 followed by DGA, no treatment (2-AAF alone) and PH. In contrast, the area (mm2) per cm2 and mean diameter of the focus were largest in the PH group then DGA followed by CCl4 and no treatment. The results indicate that the number of GST-P+ foci were not clearly affected by 3 different treatments whereas area and size of foci which represented the result of promoting effect were clearly influenced by those treatments, indicating they caused differential proliferation of initiated cells. In this respect, even though PH is the most potent procedure, DGA is also efficient and preferred to CCl4 for the non-surgical enhancing method.