%0 Journal Article %1 Pott_2007_270 %A Pott, Christian %A Henderson, Scott A %A Goldhaber, Joshua I %A Philipson, Kenneth D %D 2007 %J Ann. N. Y. Acad. Sci. %K Action Animals; Calcium Channels, Exchanger, Knockout; L-Type, Mice, Mice; Potentials; Sodium-Calcium genetics/physiology physiology; %P 270--275 %R 10.1196/annals.1387.015 %T Na$^+$/Ca$^2+$ exchanger knockout mice: plasticity of cardiac excitation-contraction coupling. %U http://dx.doi.org/10.1196/annals.1387.015 %V 1099 %X The Na$^+$/Ca$^2+$ exchanger (NCX) is the main Ca$^2+$ extrusion mechanism of the cardiac myocyte. Nevertheless, cardiac-specific NCX knockout (KO) mice are viable to adulthood. We have identified two adaptations of excitation-contraction coupling (ECC) to the absence of NCX in these animals: (a) a reduction of the L-type Ca$^2+$ current (I(Ca)) with an increase in ECC gain and (b) a shortening of the action potential (AP) to further limit Ca$^2+$ influx. Both mechanisms contribute to Ca$^2+$ homeostasis by reducing Ca$^2+$ influx while maintaining contractility. These adaptations may comprise important feedback mechanisms by which cardiomyocytes may be able to limit Ca$^2+$ influx in situations of compromised Ca$^2+$ extrusion capacity.

@article{Pott_2007_270, abstract = {The {N}a$^{+}$/{C}a$^{2+}$ exchanger (NCX) is the main {C}a$^{2+}$ extrusion mechanism of the cardiac myocyte. Nevertheless, cardiac-specific NCX knockout (KO) mice are viable to adulthood. We have identified two adaptations of excitation-contraction coupling (ECC) to the absence of NCX in these animals: (a) a reduction of the L-type {C}a$^{2+}$ current (I(Ca)) with an increase in ECC gain and (b) a shortening of the action potential (AP) to further limit {C}a$^{2+}$ influx. Both mechanisms contribute to {C}a$^{2+}$ homeostasis by reducing {C}a$^{2+}$ influx while maintaining contractility. These adaptations may comprise important feedback mechanisms by which cardiomyocytes may be able to limit {C}a$^{2+}$ influx in situations of compromised {C}a$^{2+}$ extrusion capacity.}, added-at = {2009-06-03T11:20:58.000+0200}, author = {Pott, Christian and Henderson, Scott A and Goldhaber, Joshua I and Philipson, Kenneth D}, biburl = {https://www.bibsonomy.org/bibtex/2047450f116529165280459696719f8e9/hake}, description = {The whole bibliography file I use.}, doi = {10.1196/annals.1387.015}, institution = {Department of Physiology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.}, interhash = {ba0a7a36494fbf2504fc74dc32f09b39}, intrahash = {047450f116529165280459696719f8e9}, journal = {Ann. N. Y. Acad. Sci.}, keywords = {Action Animals; Calcium Channels, Exchanger, Knockout; L-Type, Mice, Mice; Potentials; Sodium-Calcium genetics/physiology physiology;}, month = Mar, pages = {270--275}, pii = {1099/1/270}, pmid = {17446467}, timestamp = {2009-06-03T11:21:26.000+0200}, title = {{N}a$^{+}$/{C}a$^{2+}$ exchanger knockout mice: plasticity of cardiac excitation-contraction coupling.}, url = {http://dx.doi.org/10.1196/annals.1387.015}, volume = 1099, year = 2007 }