Measurement of changes in endothelial and smooth muscle Ca<sup>2+</sup> in pressurized arteries
Dora KA., Hill MA.
The use of single- and dual-wavelength Ca < sup > 2+ < /sup > -sensitive fluorescent dyes to monitor changes in endothelial and/or smooth muscle intracellular Ca < sup > 2+ < /sup > levels has provided information linking Ca < sup > 2+ < /sup > events to changes in arterial function. Here we describe the in vitro techniques used to selectively load Ca < sup > 2+ < /sup > indicators into either the endothelium or the smooth muscle of cannulated rat cremaster arteries. These vessels normally develop spontaneous myogenic tone that is largely unaffected by the loading of Ca2+ indicators or the subsequent imaging procedures. This suggests that there is minimal Ca2+ buffering or damage, and that the fluorescent indicator-loaded vessels behave similarly to unloaded preparations. Importantly, these approaches are applicable to both isobaric and isometric preparations and have been also used for the study of a number of vascular beds including cerebral, mesenteric, coronary, and skeletal muscle vasculatures. © Springer Science+Business Media, LLC 2013.