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An increase in cytoplasmic calcium (Ca(2+)) concentration ([Ca(2+)]i) is a prerequisite for the contraction of detrusor smooth muscle (DSM) cells . The increase in [Ca(2+)]i is accomplished by Ca(2+) entry mainly via voltage dependent L-type Ca(2+) channel and Ca(2+) release from intracellular stores. We report here a simulation of the processes that regulate intracellular Ca(2+) and their dependence on Ca(2+) concentration. Based on experimentally recorded data, mathematical equations for Ca(2+) current (generated mainly by L-type Ca(2+) channel) are developed along with representation of Ca(2+)ATPase pump currents. The plasma membrane Ca(2+)ATPase (PMCA) pump and sarco/endoplasmic reticulum Ca(2+)ATPase (SERCA) pump are responsible for lowering [Ca(2+)]i which leads to relaxation of smooth muscle. Our model simulates Ca(2+) current, action potential and the Ca(2+) transient response so as to reasonably mimic the experimental recordings. In novel findings, currents produced by PMCA and SERCA along with their amplitude and waveform pattern under voltage clamp condition have been predicted for DSM cells. The model has further been used to produce the Ca(2+) transient which results because of L-type Ca(2+) channel, Ca(2+) release from intracellular store, PMCA, SERCA and presence of buffer in the cytoplasm. To explore the model further, Ca(2+) transient decay rate in control condition is compared to the decay rate reached when PMCA and SERCA are inhibited. We conclude that this model can be used to describe the Ca(2+) transient response produced by the DSM cell in response to depolarization of cell membrane.

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This article discusses the clinical issues pertaining to an optimal stenting result and analyzes relevant stent structures and functions. There are five components of optimal stenting: favorable clinical features, easy stent delivery, ideal scaffolding, low stent thrombosis, and low restenosis. In straightforward cases, such as stenting in the mid‐right coronary artery with a straight proximal segment, procedural success can be achieved with any stent. In vessels with curved, tortuous proximal segments, a highly flexible stent is needed for a smooth and successful delivery. For ostial, protected left main, or aortoanastomotic lesions, stents with sufficient radial strength and good visibility are needed. The two major concerns of an interventional cardiologist choosing a stent are excellent trackability for fast delivery and low long‐term restenosis rate. In all situations, the procedural success depends on the operator's manual dexterity, experience with a particular stent design, and critical evaluation of different structural stent features to maximize benefits. Any new stent with high longitudinal flexibility, excellent scaffolding and radial strength, adequate radiopacity, complete deployment after one inflation, and that is easily recrossed and provides a good symmetrical conduit for a smooth coronary flow resulting in little tendency for thrombosis or restenosis would be today's stent of choice.