AGE-DEPENDENT CHANGES IN OXYGEN SUPPLY AND DEMAND OF RAT SPINOTRAPEZIUS MUSCLE

• Main Author: Dodhy, Sami C
• Format: Others
• Published: VCU Scholars Compass 2018
• Subjects: Cardiovascular Diseases; Circulatory and Respiratory Physiology; Disease Modeling; Physiological Processes; Translational Medical Research
• Online Access: https://scholarscompass.vcu.edu/etd/5670; https://scholarscompass.vcu.edu/cgi/viewcontent.cgi?article=6763&context=etd

Because of the aerobic nature of cellular metabolism in mammalian organisms, a continuous supply of oxygen is necessary to maintain normal physiological function. As organisms age, their metabolic rates generally decline and there are accompanying alterations in the structure and function of the microcirculation, as this part of the cardiovascular system is especially important for oxygen exchange. The overall Oxygen Transport System can be considered as being composed of two complementary components: one for Oxygen Demand and one for Oxygen Supply. The purpose of the current work is to describe the age-dependent changes in both oxygen demand and oxygen supply at the level of the microcirculation, using intravital microscopic observations of the rat spinotrapezius muscle, along with optical techniques to delineate the structural, hemodynamic and oxygenation variables needed to characterize the Oxygen Transport System in this tissue. A summary of the findings is that basal oxygen consumption gradually declined with age (from 2 to 12 months) and there were corresponding decreases in tissue blood flow, blood hemoglobin concentration and capillary surface area for oxygen exchange, so that oxygen supply and demand were generally well-matched.