Related Experiment Videos
Changes in hepatocyte ploidy in response to chromium, analyzed by computer-assisted microscopy
J C Garrison1, T U Bisel, P Peterson
1Department of Pharmacology, Toxicology and Therapeutics, Kansas University Medical Center, Kansas City 66103.
Summary
Acute chromate exposure increased liver cell ploidy in young mice, while chronic exposure caused hepatic changes like apoptosis and lobe fusion. Computer-assisted imaging enabled rapid, regional ploidy analysis.
Area of Science:
- Toxicology and Hepatopathology
- Cell Biology and Nuclear Ploidy Analysis
Background:
- Sodium dichromate exposure can induce hepatic changes, including programmed cell death (apoptosis) and liver lobe fusion.
- Hepatocyte nuclear ploidy state (proportion of diploid, tetraploid, octaploid nuclei) is a potential biomarker for liver response.
- Regional differences in ploidy exist within the liver lobule, correlating with functional zones.
Purpose of the Study:
- To investigate the effects of acute, intermediate, and chronic sodium dichromate exposure on hepatocyte nuclear ploidy in BDF1 mice.
- To evaluate the utility of computer-assisted imaging for rapid and regional ploidy determination in histological sections.
- To correlate observed hepatic changes with alterations in nuclear ploidy following chromate exposure.
Main Methods:
- Mice received single or multiple injections of sodium dichromate at varying doses and durations (acute, intermediate, chronic).
- Hepatic tissue was analyzed using computer-assisted imaging of histological sections to determine hepatocyte nuclear ploidy.
- Regional ploidy variations were assessed in relation to portal triads, central veins, and midzonal areas.
Main Results:
- Acute chromate exposure in young mice led to increased hepatocyte nuclear ploidy across all liver zones.
- Chronic exposure resulted in hepatic changes including apoptosis (periportal) and liver lobe fusion.
- Computer-assisted imaging provided rapid, regional ploidy data, superior to traditional methods, and revealed consistent regional ploidy zonation.
Conclusions:
- Acute chromate exposure significantly impacts hepatocyte nuclear ploidy, particularly in younger animals.
- Longer-term chromate exposure induces distinct hepatic pathologies, with ploidy effects potentially masked by age-related factors.
- Computer-assisted ploidy analysis is a valuable tool for studying liver toxicology and regional cellular responses.