The Hotchkiss Brain Institute
Healthy Brains for Better Lives
Research in Dr. Braun's laboratory focuses on the cellular mechanisms underlying endthelium-associated regulation of fascular smooth muscle contractility and the roles of CA2+ activated K+ channels in these processes. Three main classes of calcium activated K+channels have been identified, and are typically referred to as large, intermediate and small conductance channels (BK, IK and SK channels respectively) based on their biophysical properties. The ability of thesse channels to open in response to changes in membrane voltage and or cytosolic free calcium allows them to functions as feedback regulators of cellular processes that depend upon depolarization-induced elevations of intracellular Ca2+ (eg. muscle contraction, gene expression, secretion of neurotransmitters, and hormones). Our current research includes: 1) the structural mechanisms underlying the calcium dependence of BK-type channels; 2) the modulation of smooth muscle BK-type channel activity by endothelium via the nitric oxide/cGMP signaling pathways associated with myogenic tone; and 3) the contributions of SK and IK channels to endothelial function.