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Cyclic AMP binding activity in liver supernatants during acute ethionine intoxication
Experimental and Molecular Pathology
|June 1, 1984
Summary
Ethionine intoxication significantly increases hepatic cyclic adenosine monophosphate (cAMP) binding activity, which is reversible with adenine. This binding is influenced by ADP and ATP levels.
Area of Science:
- Biochemistry
- Hepatology
- Toxicology
Background:
- Ethionine intoxication is known to cause liver damage.
- Cyclic adenosine monophosphate (cAMP) plays a crucial role in various cellular processes.
- Understanding cAMP binding alterations in liver injury is important for therapeutic strategies.
Purpose of the Study:
- To investigate the changes in hepatic cAMP binding activity following ethionine intoxication.
- To identify the cellular fraction responsible for altered cAMP binding.
- To explore the factors influencing this binding activity.
Main Methods:
- Induction of ethionine intoxication in a model system.
- Fractionation of liver homogenates to isolate the 100,000 g supernatant.
- Measurement of cAMP binding activity.
- Administration of adenine, ADP, and ATP to assess their effects.
Main Results:
- A significant increase in hepatic cAMP binding activity was observed 4 hours post-ethionine intoxication.
- The increased binding activity was localized to the 100,000 g supernatant.
- Dialysis of control supernatant increased cAMP binding to experimental levels.
- Adenine administration reversed the intoxication-induced increase in binding.
- ADP stimulated cAMP binding, while ATP inhibited it, with equal and opposite effects at intoxication-relevant concentrations.
Conclusions:
- Ethionine intoxication leads to enhanced hepatic cAMP binding activity.
- This enhanced binding is potentially due to changes in regulatory factors within the 100,000 g supernatant.
- Adenine, ADP, and ATP play significant roles in modulating cAMP binding in the context of ethionine-induced liver injury.
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