Document Detail

Modelling the interaction among several mechanisms in the short-term arterial pressure control.
MedLine Citation:
PMID:  10977596     Owner:  NLM     Status:  MEDLINE    
A Mathematical model of the short-term arterial pressure control in humans is presented. It includes a six-compartment description of the vascular system, an elastance variable model of the pulsating heart, two groups of baroreceptors (high-pressure or sinoaortic baroreceptors and low-pressure or cardiopulmonary baroreceptors), the efferent activity in the sympathetic nerves and in the vagus, and the response of four distinct effectors (heart period, systemic peripheral resistance, systemic venous unstressed volume and heart contractility). Several experimental results reported in the physiological literature can be reproduced with the model quite well. The examples presented in this work include the effect of combined sympathetic and vagal stimulation on heart rate, the baroreflex response to mild and severe acute haemorrhages, and the baroreflex response to ventricular pacing at different rates performed during atrioventricular block. The results suggest that: i) The sympathetic nerves and the vagus interact linearly in regulating heart period. The apparent negative interaction observed experimentally can be ascribed merely to the hyperbolic relationship which links heart rate to heart period. ii) The cardiopulmonary baroafferents play a significant role in the control of systemic arterial pressure during mild haemorrhages (lower than 3-4% of the overall blood volume). In this range, they may allow arterial pressure to be maintained at its normal level without the intervention of the sinoaortic baroreceptors. In contrast, the sinoaortic baroreceptors become the major responsible of the observed cardiovascular adjustments during more severe haemorrhages, when the role of cardiopulmonary baroreceptors becomes progressively exhausted. iii) The stability margin of the closed-loop system is quite low. Increasing the static gain of the baroreceptors or reducing the rate-dependent component may result in self-sustained oscillations similar to Mayer waves.
M Ursino
Related Documents :
24827006 - Job control and ambulatory blood pressure.
23471976 - Evidence of primary aldosteronism in a predominantly female cohort of normotensive indi...
537276 - Pharmacological studies of lycorenine, an alkaloid of lycoris radiata herb.: vasodepres...
24623206 - Comparison of stroke volume variation with pulse pressure variation as a diagnostic ind...
10955386 - Elevated systolic blood pressure as a cardiovascular risk factor.
19828206 - Effect of high pressure homogenization on saccharomyces cerevisiae inactivation and phy...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Studies in health technology and informatics     Volume:  71     ISSN:  0926-9630     ISO Abbreviation:  Stud Health Technol Inform     Publication Date:  2000  
Date Detail:
Created Date:  2000-08-11     Completed Date:  2000-08-11     Revised Date:  2007-11-15    
Medline Journal Info:
Nlm Unique ID:  9214582     Medline TA:  Stud Health Technol Inform     Country:  NETHERLANDS    
Other Details:
Languages:  eng     Pagination:  139-61     Citation Subset:  T    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Arteries / physiology*
Baroreflex / physiology*
Hemorrhage / physiopathology
Models, Cardiovascular*
Pressoreceptors / physiology*
Vascular Resistance / physiology
Vasomotor System / physiology

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  The left ventricular ejection effect.
Next Document:  Short-term autonomic nervous control of the cardiovascular system: a system theoretic approach.