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Published on: August 18, 2017
Sources of cyclic nucleotides in plasma
The Journal of Clinical Investigation
|January 1, 1974
Summary
The kidneys remove cyclic nucleotides from plasma, while the lungs and small intestine add them. This study identifies key organs involved in cyclic nucleotide balance in canine plasma.
Area of Science:
- Physiology
- Biochemistry
Background:
- Cyclic nucleotides, adenosine 3',5'-monophosphate (cAMP) and guanosine 3',5'-monophosphate (cGMP), play crucial roles in cellular signaling.
- Understanding the sites of their production and removal in plasma is essential for comprehending their physiological regulation.
Purpose of the Study:
- To determine the specific organs responsible for the net production and removal of cyclic nucleotides in plasma.
- To quantify the concentrations of cAMP and cGMP in various blood vessels of anesthetized dogs.
Main Methods:
- Catheterization of multiple blood vessels in 17 anesthetized dogs.
- Measurement of arterial and venous plasma concentrations of cAMP and cGMP using radioimmunoassay.
Main Results:
- Kidneys showed significantly lower venous concentrations of both cAMP (25% lower) and cGMP (51% lower) compared to aortic levels.
- The superior mesenteric vein exhibited a marked increase in cGMP (83% greater) and a moderate increase in cAMP (16% greater).
- Pulmonary artery and hepatic vein concentrations suggested potential net addition and removal, respectively, of cyclic nucleotides.
Conclusions:
- The kidneys are identified as a major site for plasma cyclic nucleotide removal.
- The lungs and small intestine are implicated as sites of net cyclic nucleotide production and addition to plasma.
- The liver likely contributes to cyclic nucleotide removal, and overall plasma levels may result from contributions from multiple tissues.
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