Plasma angiotensins and human forearm circulation: effects of sympatho-adrenal activation

Details

Serval ID
serval:BIB_A4F8905FE5CE
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Plasma angiotensins and human forearm circulation: effects of sympatho-adrenal activation
Journal
Acta Physiologica Scandinavica
Author(s)
Kahan  T., Lindqvist  M., Nussberger  J., Melcher  A., Hjemdahi  P.
ISSN
0001-6772 (Print)
Publication state
Published
Issued date
02/1997
Volume
159
Number
2
Pages
107-11
Notes
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Feb
Abstract
Complex interactions appear to exist between the renin-angiotensin system and sympathetic neurotransmission, and sympathetic activity may influence local angiotensin II formation. Arterial and forearm venous plasma levels of angiotensin I and II were therefore studied in 11 healthy males at rest during sympathetic activation elicited by mental stress, and during adrenaline induced vasodilation. Specific assays for angiotensin-(1-8) octapeptide and for angiotensin-(1-10) decapeptide (i.e. angiotensin II and I, respectively), were used. Special precautions to minimize ex vivo formation and/or degradation of angiotensins were employed. Mental stress increased regional noradrenaline overflow three-fold, with a concomitant three-fold increase in forearm blood flow, whereas intravenous adrenaline infusion increased forearm blood flow two-fold and noradrenaline overflow four-old. There was a constant positive veno-arterial concentration difference for angiotensin I under all conditions tested, compatible with local angiotensin I formation. We found no veno-arterial concentration difference for angiotensin II or regional net angiotensin II overflow under the conditions tested. These results in the forearm circulation support previous animal experimental evidence in skeletal muscle and provide no evidence in favour of a de novo formation of angiotensin II in skeletal muscle in vivo during basal conditions. Furthermore, sympathetic nerve stimulation does not seem to enhance angiotensin II generation importantly in this vascular bed.
Keywords
Adrenal Glands/*physiology Adrenergic beta-Agonists/pharmacology Adult Angiotensin I/*blood Angiotensin II/*blood Epinephrine/pharmacology Forearm/*blood supply Humans Male Norepinephrine/blood Regional Blood Flow/drug effects Stress, Psychological/blood/physiopathology Sympathetic Nervous System/*physiology Vasodilation
Pubmed
Web of science
Create date
05/03/2008 16:39
Last modification date
20/08/2019 15:10
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