ORIGINAL RESEARCH—BASIC SCIENCEORIGINAL RESEARCH—BASIC SCIENCE: T‐Type (α1G) Low Voltage‐Activated Calcium Channel Interactions with Nitric Oxide‐Cyclic Guanosine Monophosphate Pathway and Regulation of Calcium Homeostasis in Human Cavernosal Cells

Introduction Nitric oxide‐cyclic guanosine monophosphate (NO‐cGMP)‐mediated relaxation of cavernosal smooth muscle during erection is accompanied by a decrease in intracellular calcium concentrations ([Ca2+]i). However, it is not known whether and how an increase in [Ca2+]i is responsible for (i) initiating smooth muscle contraction/detumescence following relaxation; and (ii) maintaining the penis in a flaccid state under nonstimulating conditions.