Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)

Editor

Personal info

View

About

Terms

Javascript disabled

Please enable Javascript support in your browser to use this application.

Instructions on how to enable JavaScript on different browsers can be found here: http://www.google.com/support/bin/answer.py?answer=23852.

[edit this page]

Williams, M.E. et al.

Catecholamine modulation of rapid potassium shifts during exercise.

Plasma potassium rises during muscular exercise and falls rapidly when exercise is stopped. Since the sympathoadrenal system is stimulated with exertion and both alpha- and beta-adrenergic agonists affect internal potassium homeostasis, we studied the influence of catecholamines on potassium shifts during and after exercise. Six healthy subjects were given maximal exercise stress tests under three conditions: with no medication (control), during beta-blockade with propranolol, and during alpha-blockade with phentolamine. Compared with a peak rise in plasma potassium of 1.23 +/- 0.27 mmol per liter (mean +/- S.E.M.) during the control study, propranolol caused a rise of 1.89 +/- 0.35 (P less than 0.01) and a sustained elevation during recovery. Phentolamine diminished the rise of potassium (0.70 +/- 0.21 mmol per liter; P less than 0.01) and lowered the potassium level throughout recovery. These effects of catecholamines were independent of the venous pH, the plasma bicarbonate and serum glucose levels, and urinary potassium excretion, and they did not appear to be due to insulin. High norepinephrine and epinephrine levels confirmed the release of catecholamines capable of stimulating alpha- and beta-receptors. Exercise work did not differ among the groups. beta-Adrenergic receptors appear to moderate the acute hyperkalemia of exercise, whereas alpha-adrenergic receptors act to enhance hyperkalemia and may protect against hypokalemia when exertion ceases.[1]

References

Catecholamine modulation of rapid potassium shifts during exercise. Williams, M.E., Gervino, E.V., Rosa, R.M., Landsberg, L., Young, J.B., Silva, P., Epstein, F.H. N. Engl. J. Med. (1985) [Pubmed]

Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenes Open Access Licence Privacy Policy Terms of Use apsburg

The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.