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Updated: Jun 19, 2026
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Measurement of 3-Dimensional cAMP Distributions in Living Cells using 4-Dimensional (x, y, z, and λ) Hyperspectral FRET Imaging and Analysis
Published on: October 27, 2020
Extracellular 2',3'-cAMP is a source of adenosine
Edwin K Jackson1, Jin Ren, Zaichuan Mi
1Departments of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219, USA. edj@pitt.edu
The Journal of Biological Chemistry
|October 6, 2009
Summary
Renal injury releases 2
Area of Science:
- Biochemistry
- Renal Physiology
- Cellular Metabolism
Background:
- Renal injury can lead to the release of 2',3'-cyclic adenosine monophosphate (cAMP) into the kidney interstitium.
- A novel hypothesis suggests an extracellular 2',3'-cAMP-adenosine pathway activated by renal injury.
Purpose of the Study:
- To investigate the role of extracellular 2',3'-cAMP metabolism in renal injury.
- To determine if 2',3'-cAMP can be converted to adenosine and its potential protective effects.
Main Methods:
- Isolated rat kidney perfusions with 2',3'-cAMP and metabolic inhibitors.
- In vivo renal artery infusions of 2',3'-cAMP, 2'-AMP, and 3'-AMP in rats.
- Measurement of secreted and excreted adenine nucleotides and adenosine.
Main Results:
- Infusions of 2',3'-cAMP significantly increased secretion of 3'-AMP, 2'-AMP, adenosine, and inosine in isolated kidneys.
- Renal injury with metabolic inhibitors elevated interstitial 2',3'-cAMP and its metabolites.
- 2'-AMP and 3'-AMP infusions increased adenosine and inosine secretion as efficiently as 5'-AMP.
Conclusions:
- Extracellular 2',3'-cAMP is metabolized to adenosine, with 2'-AMP and 3'-AMP being efficient precursors.
- This pathway may protect tissues by reducing pro-apoptotic 2',3'-cAMP and increasing protective adenosine.
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