Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Physiology
Muscle Metaboreflex Control Of Cardiovascular Function In Hypertension, Marty Daniel Spranger
Muscle Metaboreflex Control Of Cardiovascular Function In Hypertension, Marty Daniel Spranger
Wayne State University Dissertations
Skeletal muscle ischemia during or immediately following exercise leads to the accumulation of metabolites (e.g., lactate, proton and diprotonated phosphate) which activate chemoreceptive afferents within the muscle leading to a reflex increase in sympathetic outflow generating substantial increases in mean arterial pressure (MAP), cardiac output (CO) and heart rate (HR) - termed the muscle metaboreflex. When the reflex is activated during submaximal dynamic exercise, the pressor response occurs via increased CO with no net peripheral vasoconstriction. When metaboreflex activation is sustained during the recovery from exercise (i.e., post-exercise muscle ischemia - (PEMI)), whereas MAP remains elevated for as long as …
Muscle Metaboreflex Control Of Coronary Blood Flow And Ventricular Contractility During Dynamic Exercise In Normal And Heart Failure Conditions, Matthew Coutsos
Muscle Metaboreflex Control Of Coronary Blood Flow And Ventricular Contractility During Dynamic Exercise In Normal And Heart Failure Conditions, Matthew Coutsos
Wayne State University Dissertations
Muscle metaboreflex activation during dynamic exercise induces a substantial increase in cardiac work and oxygen demand via a significant increase in heart rate, ventricular contractility and afterload. This increase in cardiac work should cause coronary metabolic vasodilation. However, little if any coronary vasodilation is observed due to concomitant sympathetically induced coronary vasoconstriction. In heart failure, cardiac output does not increase with MMA presumably due to impaired left ventricular contractility, and large decreases in coronary vascular conductance are observed. The purpose of this dissertation is to determine whether the muscle metaboreflex-induced restraint of coronary vasodilation functionally limits coronary blood flow and …