Some aspects of the chemical and cellular composition of adult rat liver

Abstract

1. 1. Jacob and Bhargava's method of preparing rat hepatic cell suspensions gives a recovery of 84–93 per cent (mean 89 ± 0.8 per cent) of the hepatic parenchymal cells present initially in adult rat liver. 2. 2. The liver of 3–14-month-old rats contains 196–469 × 10 6 (mean 320 ± 6 × 10 6) hepatic cells per g dry weight of liver, or 52–135 × 10 6 (mean 81 ± 28 × 10 6) hepatic cells per g wet weight of liver, while the number of non-hepatic cells is 319–738 × 10 6 (mean 450 ± 41 × 10 6) per g dry weight of liver, or 75–197 × 10 6 (mean 114 ± 36 × 10 6) per g wet weight of liver. The hepatic cells represent 29–55 per cent (mean 40.1 ± 2.7 per cent) and the non-hepatic cells 45–71 per cent (59.9 ± 2.7 per cent) of the total cell population of liver. The number of hepatic cells per g dry weight of liver decreases with increase in dry weight of liver; no significant correlation was found between the dry weight of liver and the number of non-hepatic cells per g dry weight of liver. 3. 3. The number of hepatic and non-hepatic cells in the whole liver is 310–863 × 10 6 (mean 514 ± 117 × 10 6) and 478–1080 × 10 6 (mean 751 ± 62 × 10 6), respectively. 4. 4. The total number of cells in liver is 546–1040 × 10 6 (mean 778 ± 149 × 10 6) per g dry weight of liver, or 126–277 × 10 6 (mean 197 ± 42 × 10 6) per g wet weight of liver, or 1030–1790 × 10 6 (mean 1250 ± 247 × 10 6) per liver. 5. 5. The dry weight of hepatic cells varies from 0.75–2.42 mg (mean 1.30 ± 0.12 mg) per 10 6 cells. 6. 6. On an average, the hepatic cells appear to be responsible for a little less than half, the non-hepatic cells for less than 5 per cent, and the noncellular material for about half the dry weight of liver. The percentage of non-cellular material in liver (on dry weight basis) increases with an increase in the dry weight of liver and a decrease in the number of hepatic cells per unit weight of liver. 7. 7. The livers of 3–9-month-old animals contain 12–21 per cent binucleated hepatic cells and less than 1 per cent tri- and tetra-nucleated hepatic cells. The number of binucleated cells increases with age. 8. 8. The volume of a hepatic cell usually varies between 5100 and 20,100 cμ; only a small fraction of the hepatic cells of liver have a volume which is outside this range. The average volume of hepatic cells from any animal varies between 8630–12,300 cμ (mean 10,600 ± 1480 cμ) and increases with increase in the dry weight of liver. 9. 9. Liver contains 0.57–0.87 per cent (mean 0.73 ± 0.03 per cent) DNA per g dry weight of liver, or 0.13–0.23 per cent (mean 0.18 ± 0.04 per cent) DNA per g wet weight of liver, or 9–18 mg (mean 12.2 ± 0.8 mg) DNA per liver. 10. 10. The hepatic cells in liver contain a little more than half (43–76 per cent; mean 58.6 ± 2.8 per cent), and the other cells a little less than half (25–57 per cent; mean 41.4 ± 2.8 per cent) of the total DNA of liver. 11. 11. The DNA content of average hepatic cell varies between 12.1 and 19.7 × 10 −12 g, and of an average hepatic cell nucleus between 11.6 and 15.2 × 10 −12 g. 12. 12. The results are discussed vis-a-vis earlier observations in respect of the above-mentioned parameters of liver.