Table 2

Proliferative parameters

Twelve lean and 12 ob/ob mice of the same age and gender were given injections i.p. of BrdUrd. Two h later, the mice were killed; a piece of each liver was fixed in formalin, paraffin embedded, sectioned, and examined for BrdUrd (+) hepatocyte nuclei. Ten randomly-selected ×400 microscope fields were examined on each section, and the average number of labeled hepatocyte nuclei per 1000 hepatocytes was determined for each mouse. Results shown are the mean (+SE) data obtained from 12 mice from each group. In four mice from each group, liver cell nuclei were isolated from the remaining liver tissues and stained with propidium iodide. Flow cytometery was performed to determine the hepatocyte nuclear DNA content. The results from one representative lean and ob/ob mouse/group are displayed in Fig. 4 <$REFLINK> . The mean cell cycle distribution data from the entire group of lean and ob/ob mice are displayed as % nuclei in each phase of the cell cycle. Diploid cell cycle = G0−G1 (2n) and S–G2-M (4n); hyperdiploid cell cycle = G0−G1 (8n) and S–G2-M (16n). All of the differences between lean and ob/ob groups are significant with P < 0.05.
MiceLiver histologyFlow cytometry of liver nuclei
BrdUrd (+) hepatocyte nucleiDiploid cycleHyperdiploid cycle
G0−G1S-G2−MG0−G1S-G2−M
Lean2.3 ± 0.397.72.389.210.8
ob/ob 3.4 ± 0.396.43.683.516.5