Abstract 18100: Vascular Smooth Muscle Kv1.5 Channels Contribute to Coronary Metabolic Dilation

Many mechanisms are known to contribute to the regulation of coronary blood flow, including redox sensing voltage-gated potassium (Kv) channels. Previously we found, that one member of the Kv family, Kv1.5 channels, play a critical role in coupling myocardial blood flow to cardiac work. Specifically mice with global knockout of Kv1.5 channels (Kv1.5 -/-) have blunted metabolic dilation; however a limitation of this observation is that Kv1.5 channels are expressed in many cell types, e.g., cardiac myocytes, neurons, in addition to vascular smooth muscle (VSMC) so we cannot decisively conclude a role for VSMC Kv1.5 channels in this process. Accordingly, we hypothesized that expression of Kv 1.5 channels in VSMC in Kv1.5 -/- rescues the impaired metabolic dilatation. We created double transgenic mice (Tg) with doxycycline (Dox) inducible Kv1.5 channel expression in VSMC (SM22 promoter). To stimulate expression of Kv1.5 channels, mice were given Dox for 7 days. Myocardial blood flow (MBF) and hemodynamic meas...