University of Surrey

Test tubes in the lab Research in the ATI Dance Research

The use of isolated hepatocytes to study the toxic effects of chemicals.

Gwynn, Jennie. (1981) The use of isolated hepatocytes to study the toxic effects of chemicals. Doctoral thesis, University of Surrey (United Kingdom)..

[img]
Preview
Text
10798499.pdf
Available under License Creative Commons Attribution Non-commercial Share Alike.

Download (8MB) | Preview

Abstract

Some characteristics of rat hepatocytes, isolated by a non-perfusion technique, have been examined in order to validate their use for the investigation of chemically induced toxicity. Untreated hepatocytes synthesized protein, RNA and GSH and metabolised exogenous substrates. GSH was depleted during isolation but active resynthesis was evident on incubation in complete culture medium. The levels of GSH, ATP and cyclic AMP were similar to those reported in the literature for hepatocytes isolated by perfusion. Hence the hepatocytes were shown to possess a number of in vivo characteristics. Although there was an inherent variability between individual preparations characterised by the variability in, and lack of correlation between, the rate of protein synthesis, cell yield and viability, the effect of a number of xenobiotics were investigated. Paracetamol induced a rapid fall in ATP, dose-dependent inhibition of protein, RNA synthesis, and the metabolism of 7-EC, depletion of GSH and covalent binding of drug related material to protein. Exposure of cultured hepatocytes to 40mM paracetamol for < 4 hrs produced reversible inhibition of protein synthesis, but cell death was the result of a longer exposure. Safrole and phenobarbitone also induced a rapid fall in ATP levels followed by dose-dependent inhibition of protein and RNA synthesis. This was, therefore, a common sequence of events in response to a toxic insult but was unlikely to be the direct cause of cell death. The activities of 7-EC O-deethylase, NADPH[2] diaphorase, SDH and G6PDH were all increased in cultures treated with 2mM phenobarbitone (a concentration which did not cause cell death). Paracetamol also caused increases in NADPH[2] diaphorase activity. The effects of these xenobiotics in hepatocytes were compared and discussed. It was concluded that the cause of cell death was not identified and that it was unlikely to be due to one factor alone but to a combination of factors dependent on the level and duration of toxic insult and a decreased ability of the cell to repair damage. With further refinements cultured hepatocytes should provide a useful model for the investigation of mechanisms of chemically induced toxicity.

Item Type: Thesis (Doctoral)
Divisions : Theses
Authors :
NameEmailORCID
Gwynn, Jennie.
Date : 1981
Contributors :
ContributionNameEmailORCID
http://www.loc.gov/loc.terms/relators/THS
Additional Information : Thesis (Ph.D.)--University of Surrey (United Kingdom), 1981.
Depositing User : EPrints Services
Date Deposited : 22 Jun 2018 13:01
Last Modified : 06 Nov 2018 16:52
URI: http://epubs.surrey.ac.uk/id/eprint/847478

Actions (login required)

View Item View Item

Downloads

Downloads per month over past year


Information about this web site

© The University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom.
+44 (0)1483 300800