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Updated: Aug 29, 2026

Applications of Spatio-temporal Mapping and Particle Analysis Techniques to Quantify Intracellular Ca2+ Signaling In Situ
Published on: January 7, 2019
[Cytosolic calcium dynamics and smooth muscle contraction.III Plasmalemmal calcium fluxes]
D N Serban1, Lăcrămioara Serban, Simona Mihaela Slătineanu
1Disciplina de Fiziologie, Facultatea de Medicină, Universitatea de Medicină şi Farmacie Gr.T. Popa Iaşi.
Abstract:
Smooth muscle contractile activity depends upon cytosolic Ca2+, the Ca(2+)-sensitivity of actin-myosin interaction and several auxiliary mechanisms. This section presents the plasmalemmal Ca2+ fluxes in relation with the functional structure of their supportive proteins and the contractile impact. Summaries of classical data are accompanied by examples of recent advances. Ca2+ influx occurs mainly via the L and T types of voltage-operated Ca2+ channels, the store-operated Ca2+ channels and the non-selective cation channels (operated by membrane receptors or mechanical stimuli). The plasmalemmal Ca2+ ATPase and Na/Ca antiport function to limit increases in cytosolic Ca2+; Na/Ca effect is opposite when driven to operate in the reverse mode.
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