Publication Date

2012

Document Type

Thesis

Committee Members

Timothy Cope (Other), Andrew Hsu (Other), James Olson (Committee Member), Robert Putnam (Committee Member), Christopher Wyatt (Advisor)

Degree Name

Master of Science (MS)

Abstract

Carotid bodies (CB) are paired, oxygen-sensing organs located in the bifurcation of the carotid artery that act as peripheral chemoreceptors in the detection of hypoxic, hypercapnic and acidotic levels in the arterial blood. CBs respond to these fluctuations in blood gases by initiating firing of the carotid sinus nerve. This ultimately results in the appropriate ventilatory change to restore blood gases to their physiological levels. Studies have shown that the hypoxic response of the carotid body in juvenile mammals is low, but as maturation occurs this response is strengthened and clearly exhibited in adults. One theory suggests mitochondria play a vital role in the oxygen sensitivity of Type I cells in carotid bodies. The experimental hypothesis of this project is that mitochondria in the oxygen sensing Type I cells of rat carotid bodies change in number and /or distribution during the development of the acute hypoxic ventilatory response. Type I cells were isolated from juvenile (4-6 days) and mature (14-16 days) rat carotid bodies and loaded with mitotracker to quantify mitochondrial content. Data obtained demonstrated a significant reduction in the total volume of mitochondria in Type I cells during development which was not paralleled by a fall in metabolic rate, indicating an increase in the rate of mitochondrial oxidative phosphorylation. These findings suggest that change in mitochondrial content during the development of the hypoxic response might be crucial for this mechanism's development.

Page Count

90

Department or Program

Department of Neuroscience, Cell Biology & Physiology

Year Degree Awarded

2012


Included in

Anatomy Commons

Share

COinS