Robert S. Fitzgerald
The Johns Hopkins University, USA
Title: Interoreceptors and cardiopulmonary pathology
Biography
Biography: Robert S. Fitzgerald
Abstract
Chronic Heart Failure (CHF) is among the several cardiopulmonary disorders that are responsible for 74.5% of deaths world wide according to the report from WHO in 2013. The malfunctioning carotid body (CB) is responsible for increasing output from the sympathetic nervous system (SNS). This increase affects breathing patterns, cardiac performance, kidney function. Experiments in animal models have uncovered ways in which the CB can return to normal. It is perhaps an opportune time to understand this interoreceptor, arguably the most important in the organism. Located bilaterally at the junction of the carotid arteries bifurcation into external and internal branches, this structure in humans is tiny…weighing 18 mg. Yet measured blood flow through the feline version exceeds 2 L/min/100gm tissue. CBs are the sole detector of decreases in PaO2; it also is stimulated by increases in PaCO2 and H+, and glucopenia. Stimulation produces reflex responses in the cardiopulmonary, endocrine, and renal systems. CHF reduces the production of nitric oxide (NO) in the CBs, allowing for a greater release of ACh and ATP which stimulates the increase in SNS output. Efforts to reduce CB output in both humans and animal models have uncovered three techniques which show promise. Reduction in CB neural output is the key factor to restore normal cardiac function and reduce hypertension.