Progressive muscle metaboreflex activation gradually decreases spontaneous heart rate baroreflex sensitivity during dynamic exercise
| Autor: | ZhenHua Li, Javier A. Sala-Mercado, Tomoko Ichinose, Masashi Ichinose, Dominic Fano, Donal S. O'Leary, Elizabeth J. Dawe, Matthew Coutsos |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Male
medicine.medical_specialty Cardiac output Physiology Blood Pressure Physical exercise Baroreflex Autonomic Nervous System Ventricular Function Left Dogs Heart Rate Physical Conditioning Animal Physiology (medical) Internal medicine Reflex Heart rate medicine Animals Cardiac Output Muscle Skeletal Feedback Physiological Chemistry Skeletal muscle Articles Blood flow Endocrinology Blood pressure medicine.anatomical_structure Models Animal Circulatory system Female Cardiology and Cardiovascular Medicine |
| Zdroj: | American Journal of Physiology-Heart and Circulatory Physiology. 298:H594-H600 |
| ISSN: | 1522-1539 0363-6135 |
| DOI: | 10.1152/ajpheart.00908.2009 |
| Popis: | Ischemia of active skeletal muscle elicits a pressor response termed the muscle metaboreflex. We tested the hypothesis that in normal dogs during dynamic exercise, graded muscle metaboreflex activation (MMA) would progressively attenuate spontaneous heart rate baroreflex sensitivity (SBRS). The animals were chronically instrumented to measure heart rate (HR), cardiac output (CO), mean and systolic arterial pressure (MAP and SAP), and left ventricular systolic pressures (LVSP) at rest and during mild or moderate treadmill exercise before and during progressive MMA [via graded reductions of hindlimb blood flow (HLBF)]. SBRS [slopes of the linear relationships (LRs) between HR and LVSP or SAP during spontaneous sequences of ≥3 consecutive beats when HR changed inversely vs. pressure] decreased during mild exercise from the resting values (−5.56 ± 0.86 vs. −2.67 ± 0.50 beats·min−1·mmHg−1, P −1·mmHg−1, P |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|