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Updated: Jul 21, 2026
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Determination of Tolerable Fatty Acids and Cholera Toxin Concentrations Using Human Intestinal Epithelial Cells and BALB/c Mouse Macrophages
Published on: May 30, 2013
Alkaline phosphatase. Possible induction by cyclic AMP after cholera enterotoxin administration
The Journal of Clinical Investigation
|November 1, 1973
Summary
Cyclic adenosine monophosphate (cyclic AMP) likely induces rat liver alkaline phosphatase. This induction is mediated by cholera enterotoxin and glucagon, but not by bile duct ligation, suggesting multiple induction pathways.
Area of Science:
- Biochemistry
- Molecular Biology
- Hepatology
Background:
- Alkaline phosphatase is crucial in various physiological processes.
- The regulatory mechanisms of rat liver alkaline phosphatase induction are not fully understood.
- The role of cyclic adenosine monophosphate (cyclic AMP) in this process requires further elucidation.
Purpose of the Study:
- To investigate the potential role of cyclic AMP as a chemical inducer of rat liver alkaline phosphatase.
- To determine the signaling pathways involved in the regulation of hepatic alkaline phosphatase activity.
Main Methods:
- Intravenous administration of cholera enterotoxin and glucagon to rats.
- Measurement of hepatic adenyl cyclase, cyclic AMP, and alkaline phosphatase activities.
- Inhibition studies using cycloheximide.
- Bile duct ligation model to investigate alternative induction pathways.
Main Results:
- Cholera enterotoxin and glucagon significantly increased hepatic adenyl cyclase and cyclic AMP levels, preceding a rise in alkaline phosphatase.
- Cycloheximide inhibited the rise in alkaline phosphatase, indicating a requirement for protein synthesis.
- Bile duct ligation increased alkaline phosphatase but did not affect cyclic AMP levels.
- Combined treatments showed no additive effects, suggesting a common final pathway.
Conclusions:
- Cyclic AMP acts as an inducer of rat liver alkaline phosphatase.
- Cholera enterotoxin-induced stimulation of hepatic alkaline phosphatase is mediated by cyclic AMP.
- Bile duct ligation-induced alkaline phosphatase increase is independent of cyclic AMP.
- Rat liver alkaline phosphatase can be induced through at least two distinct mechanisms, one involving cyclic AMP and another independent of it.
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