A quantitative model for linking Na+/Ca2+ exchanger to SERCA during refilling of the sarcoplasmic reticulum to sustain [Ca2+] oscillations in vascular smooth muscle |
| |
Authors: | Fameli Nicola van Breemen Cornelis Kuo Kuo-Hsing |
| |
Affiliation: | aDepartment of Anesthesiology, Pharmacology and Therapeutics, The University of British Columbia, 2176, Health Sciences Mall, Vancouver, BC, Canada V6T 1Z3 |
| |
Abstract: | We have developed a quantitative model for the creation of cytoplasmic Ca2+ gradients near the inner surface of the plasma membrane (PM). In particular we simulated the refilling of the sarcoplasmic reticulum (SR) via PM–SR junctions during asynchronous [Ca2+]i oscillations in smooth muscle cells of the rabbit inferior vena cava. We have combined confocal microscopy data on the [Ca2+]i oscillations, force transduction data from cell contraction studies and electron microscopic images to build a basis for computational simulations that model the transport of calcium ions from Na+/Ca2+ exchangers (NCX) on the PM to sarcoplasmic/endoplasmic reticulum Ca2+ ATPase (SERCA) pumps on the SR as a three-dimensional random walk through the PM–SR junctional cytoplasmic spaces. Electron microscopic ultrastructural images of the smooth muscle cells were elaborated with software algorithms to produce a very clear and dimensionally accurate picture of the PM–SR junctions. From this study, we conclude that it is plausible and possible for enough Ca2+ to pass through the PM–SR junctions to replete the SR during the regenerative Ca2+ release, which underlies agonist induced asynchronous Ca2+ oscillations in vascular smooth muscle. |
| |
Keywords: | mml37" > text-decoration:none color:black" href=" /science?_ob=MathURL&_method=retrieve&_udi=B6WCC-4NF2NJ8-1&_mathId=mml37&_user=10&_cdi=6735&_rdoc=6&_acct=C000069468&_version=1&_userid=6189383&md5=8e512eab4b8a67be60fb841ccdad0e6b" title=" Click to view the MathML source" alt=" Click to view the MathML source" >Ca2+ oscillations Calcium signaling Vascular smooth muscle Sarcoplasmic reticulum Stochastic model |
本文献已被 ScienceDirect PubMed 等数据库收录! |