Norepinephrine and epinephrine responses to physiological and pharmacological stimulation in chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is characterized by fatigue lasting 6 months or longer. CFS has been associated with a disturbed (re-)activity of the autonomic nervous system. However, the sympathetic adrenomedulla (SAM) remains under-examined in CFS.

To investigate SAM reactivity, we implemented a submaximal cycle ergometry (ERGO) and a pharmacological test (Insulin Tolerance Test, ITT) in 21 CFS patients and 20 age-, sex-, and BMI-matched controls. Plasma norepinephrine and epinephrine were collected once before and twice after the tests (+10/+20, and +30 min).

Lower baseline levels and attenuated responses of epinephrine to the ERGO were found in CFS patients compared to controls, while the groups did not differ in their responses to the ITT.

To conclude, we found evidence of altered sympathetic-neural and SAM reactivity in CFS. Exercise stress revealed a subtle catecholaminergic hyporeactivity in CFS patients. It is conceivable that inadequate catecholaminergic responses to physical exertion might contribute to CFS symptoms.

Copyright © 2013 Elsevier B.V. All rights reserved.

 

Source: Strahler J, Fischer S, Nater UM, Ehlert U, Gaab J. Norepinephrine and epinephrine responses to physiological and pharmacological stimulation in chronic fatigue syndrome. Biol Psychol. 2013 Sep;94(1):160-6. doi: 10.1016/j.biopsycho.2013.06.002. Epub 2013 Jun 13. https://www.ncbi.nlm.nih.gov/pubmed/23770415

 

Hormonal responses to exercise in chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is a debilitating disease characterized by severe, unexplained fatigue and postexertional exacerbation of symptoms. We examined basal endocrine function in a group of CFS patients and a carefully matched group of sedentary controls. The subjects then completed a graded, maximal exercise test on a treadmill, and additional blood samples were drawn 4 min and a day after the end of exercise.

There were no differences in basal hormone levels before exercise. Plasma adrenocorticotropin, epinephrine, prolactin and thyrotropin responses 4 min after exercise were lower in the CFS group, but the growth hormone response may have been exaggerated, and the plasma norepinephrine response was similar to that in controls.

The next day, there were no differences in hormone levels between the groups, which suggests that long-term changes in endocrine function are unlikely to be a cause of the prolonged fatigue that occurs in CFS patients after a bout of exertion.

 

Source: Ottenweller JE, Sisto SA, McCarty RC, Natelson BH. Hormonal responses to exercise in chronic fatigue syndrome. Neuropsychobiology. 2001 Jan;43(1):34-41. http://www.ncbi.nlm.nih.gov/pubmed/11150897