Dr. Ruth Heidelberger
The University of Texas Health Science Center at Houston
McGovern Medical School
Department of Neurobiology and Anatomy
The research in my laboratory is directed at understanding the mechanisms that underlie and regulate neurotransmitter exocytosis. As a model system, we study exocytosis in bipolar neurons isolated from vertebrate retina. These neurons have unusually large presynaptic terminals that allow us to place an electrode directly onto the presynaptic ending to electrically monitor synaptic vesicle fusion and recovery in real-time. As a second model system, we work with neuroendocrine cells of the adrenal medulla. The use of these two model systems allows us to study and compare exocytosis of small, clear-core synaptic vesicles (bipolar cells) with exocytosis of large, dense-core granules (adrenal chromaffin cells). Current studies are directed at understanding the role of ATP in neurotransmitter release and synaptic vesicle cycling and at identifying presynaptic sites of regulation and modulation of exocytosis. The role of local retinal circuit interactions on neurotransmitter release and the consequences of this modulation on visual processing are also considered.
A tutorial in my laboratory could provide experience in single-cell physiology using patch-clamp recording technique, measurement of membrane capacitance as an assay of synaptic vesicle fusion, fluorescence measurement of intracellular calcium, flash-photolysis of caged-compounds, and carbon-fiber amperometry.