| The 'body fluid pressure control system' relies on the Renin-Angiotensin-aldosterone system: balance studies in freely moving dogs. | |
| | |
MedLine Citation:
|
PMID: 15854148 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
1. The physiological role of the 'renal body fluid pressure control system', including the intrarenal mechanism of 'pressure natriuresis', is uncertain. 2. Balance studies in freely moving dogs address the following questions: (i) what is the physiological contribution of pressure natriuresis to the control of total body sodium (TBS); (ii) to what extent is long-term mean arterial blood pressure (MABP) determined by TBS and total body water (TBW); and (iii) during Na accumulation, is Na stored in an osmotically inactive form? 3. Diurnal time-courses of Na excretion (U(Na)V) and MABP reveal no correlation. Spontaneous MABP changes do not affect U(Na)V. The long-term 20% reduction of renal perfusion pressure (RPP) results in Na retention via pressure-dependent stimulation of the renin-angiotensin-aldosterone system (RAAS), not via a pressure natriuresis mechanism. Prevention of pressure natriuresis does not result in ongoing Na retention when the RAAS is operative. The long-term 20% elevation of RPP induced by sustained TBS elevation facilitates Na excretion via pressure natriuresis, but does not restore TBS to normal. 4. Changes in TBW correlate well with changes in TBS (r(2) = 0.79). This correlation is even closer when concomitant changes in total body potassium are also considered (r(2) = 0.91). 5. With normal or elevated TBW, long-term MABP changes correlate well with TBW changes (r(2) = 0.69). At lowered TBW, no correlation is found. 6. In conclusion, the physiological role of pressure natriuresis is limited. Pressure natriuresis does not appear to be operative when RPP is changed from -20 to +10% and neurohumoral control of U(Na)V is unimpeded. Within this range, pressure-dependent changes in the RAAS mediate the effects of changes in RPP on U(Na)V. Pressure natriuresis may constitute a compensating mechanism under pathophysiological conditions of substantial elevation of RPP. A large portion of the long-term changes in MABP are attributable to changes in TBW. The notion of osmotically inactive Na storage during Na accumulation appears to be invalid. |
| | |
Authors:
|
Erdmann Seeliger; Thomas Wronski; Mechthild Ladwig; Till Rebeschke; Pontus B Persson; H Wolfgang Reinhardt |
Related Documents
:
|
6521358 - Cardiovascular and adrenal sensitivity to angiotensin ii in essential hypertension. 19021028 - Aldosterone as an independent factor in cerebrovascular damage. 1188918 - Renal effects of prostaglandin e1 in hypertensive patients. 16410298 - Hemodynamic, hormonal, and renal actions of adrenomedullin-2 in normal conscious sheep. 4443868 - Direct monitoring of arterial blood pressure in depressed and normal newborn infants du... 2272708 - Effect of calcium and calcium blockers in hypertension. |
Publication Detail:
|
Type: Comparative Study; Journal Article; Research Support, Non-U.S. Gov't |
Journal Detail:
|
Title: Clinical and experimental pharmacology & physiology Volume: 32 ISSN: 0305-1870 ISO Abbreviation: Clin. Exp. Pharmacol. Physiol. Publication Date: 2005 May-Jun |
Date Detail:
|
Created Date: 2005-04-27 Completed Date: 2006-01-17 Revised Date: 2006-11-15 |
Medline Journal Info:
|
Nlm Unique ID: 0425076 Medline TA: Clin Exp Pharmacol Physiol Country: Australia |
Other Details:
|
Languages: eng Pagination: 394-9 Citation Subset: IM |
Affiliation:
|
Institut für Physiologie, Charité Campus Mitte, Berlin, Germany. erdmann.seeliger@charite.de |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Animals Blood Pressure / physiology* Body Fluids / physiology* Dogs Female Movement / physiology Natriuresis / physiology Renin-Angiotensin System / physiology* Water-Electrolyte Balance / physiology* |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Hypothesis: set-points and long-term control of arterial pressure. A theoretical argument for a long...
Next Document: Mechanisms mediating pressure natriuresis: what we know and what we need to find out.