Tumor necrosis factor alpha in various tissues of insulin-resistant obese Koletsky rats: relations to insulin receptor characteristics
Language English Country Czech Republic Media print
Document type Journal Article, Research Support, Non-U.S. Gov't
PubMed
10470871
Knihovny.cz E-resources
- MeSH
- Insulin metabolism MeSH
- Insulin Resistance * genetics MeSH
- Liver metabolism MeSH
- Muscle, Skeletal metabolism MeSH
- Rats MeSH
- Rats, Mutant Strains MeSH
- Obesity metabolism MeSH
- Rats, Wistar MeSH
- Receptor, Insulin metabolism MeSH
- Retroperitoneal Space MeSH
- Tumor Necrosis Factor-alpha metabolism pharmacology MeSH
- Adipose Tissue metabolism MeSH
- Protein-Tyrosine Kinases metabolism MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Insulin MeSH
- Receptor, Insulin MeSH
- Tumor Necrosis Factor-alpha MeSH
- Protein-Tyrosine Kinases MeSH
Tumor necrosis factor alpha (TNFalpha) was found to be significantly increased in skeletal muscles and retroperitoneal fat of obese insulin-resistant Koletsky rats as compared to control Wistar rats. This increase was accompanied by a depression of insulin receptor protein tyrosine kinase (PTK) activity. Neither the insulin-binding capacity nor insulin receptor affinity were related to this TNFalpha increase in these tissues. In the liver, no significant changes of TNFalpha content and only a lowering of insulin-binding capacity were found. It is concluded that an increased TNFalpha content in muscles and fat (but not in the liver) contributes to insulin resistance by lowering insulin receptor protein tyrosine kinase activity, while other insulin receptor characteristics (insulin-binding capacity and affinity of insulin receptors to the hormone) do not seem to be influenced by this factor.
