My Research

My research focuses on neuronal regulation of cardiac function. Specifically, I am interested in how neurotransmitters (chemicals released by nerve cells to communicate with one another) can modulate the activity of neurons located within the heart which in turn regulate heart rate and the strength of heart contractions. To investigate these questions, I make use of several different neurobiological techniques, including immunohistochemistry, electrophysiology, and biochemical techniques. Currently, I'm investigating two specific questions.

The first question is how the nervous system and the immune system interact in the control of cardiac function. For example, an allergic reaction involving the heart (cardiac anaphylaxis) appears to directly affect the activity of neurons located within the heart itself. In order to better understand the specific mechanisms and consequences of this phenomenon, I examine the localization of specific neurotransmitters and immune cells known to be involved in this reaction using immunohistochemical techniques. I can also measure the changes in electrical activity of individual neurons in response to different inflammatory agents using electrophysiological techniques:

The other question I'm studying in how neuropeptides (small chains of amino acids synthesized and released by nerve cells) can regulate cardiac function. Several different neuropeptides have been localized in nerve fibers innervating cardiac tissue and the neurons located within the heart. One hypothesis is that these neuropeptides are involved in local, reflex control of cardiac function. For these studies, I use the two different amphibians, the mudpuppy (Necturus maculosus) and the axolotl (Ambystoma mexicanum), as model systems. This amphibian has been used extensively to study neuronal control and integration in the regulation of cardiac function. Again, I employ the techniques of immunohistochemistry and electrophysiology to answer specific questions.