An estimate of the calcium content of the sarcoplasmic reticulum in rat ventricular myocytes Export

@article{citeulike:2883983, abstract = {The aim of this paper was to estimate the Ca content of the sarcoplasmic reticulum (s.r.) and to compare this with the amount of Ca which enters the cell via the calcium current in systole. The s.r. Ca content was measured electrophysiologically in voltage-clamped rat ventricular myocytes. Rapid application of caffeine produced a transient increase of [Ca2+]i which was accompanied by a transient inward Na-Ca exchange current. The integral of this current gives a measure of the Ca2+ pumped out of the cell by Na-Ca exchange. Ni2+ (5 mM) inhibited the current and decreased the rate of fall of [Ca2+]i to 32\% of the control suggesting that Na-Ca exchange is responsible for 68\% of Ca removal from the cytoplasm following the addition of caffeine. Correcting for the Na-Ca independent Ca removal suggests that the s.r. Ca content is equivalent to about 120 µmol per litre cell. Furthermore we estimate that, during systole, Ca entry into the cell via the sarcolemmal calcium current is equal to about 6 \% of the Ca content of the s.r.}, author = {Varro, A. and Negretti, N. and Hester, S. B. and Eisner, D. A.}, citeulike-article-id = {2883983}, citeulike-linkout-0 = {http://dx.doi.org/10.1007/BF00374975}, day = {1}, doi = {10.1007/BF00374975}, journal = {Pfl\"{u}gers Archiv European Journal of Physiology}, keywords = {barrium, caffeine, calcium-transient, electrophysiology, indo-1, inward, na-ca2-exchanger, ni, rat, rectifier, sr-load, ventricular-myocytes}, month = {April}, number = {1}, pages = {158--160}, posted-at = {2008-06-12 00:31:22}, priority = {0}, title = {An estimate of the calcium content of the sarcoplasmic reticulum in rat ventricular myocytes}, url = {http://dx.doi.org/10.1007/BF00374975}, volume = {423}, year = {1993} }

TY - JOUR ID - citeulike:2883983 L3 - citeulike-article-id:2883983 N2 - The aim of this paper was to estimate the Ca content of the sarcoplasmic reticulum (s.r.) and to compare this with the amount of Ca which enters the cell via the calcium current in systole. The s.r. Ca content was measured electrophysiologically in voltage-clamped rat ventricular myocytes. Rapid application of caffeine produced a transient increase of [Ca2+]i which was accompanied by a transient inward Na-Ca exchange current. The integral of this current gives a measure of the Ca2+ pumped out of the cell by Na-Ca exchange. Ni2+ (5 mM) inhibited the current and decreased the rate of fall of [Ca2+]i to 32% of the control suggesting that Na-Ca exchange is responsible for 68% of Ca removal from the cytoplasm following the addition of caffeine. Correcting for the Na-Ca independent Ca removal suggests that the s.r. Ca content is equivalent to about 120 µmol per litre cell. Furthermore we estimate that, during systole, Ca entry into the cell via the sarcolemmal calcium current is equal to about 6 % of the Ca content of the s.r. IS - 1 JF - Pflügers Archiv European Journal of Physiology EP - 160 TI - An estimate of the calcium content of the sarcoplasmic reticulum in rat ventricular myocytes VL - 423 SP - 158 KW - barrium KW - caffeine KW - calcium-transient KW - electrophysiology KW - indo-1 KW - inward KW - na-ca2-exchanger KW - ni KW - rat KW - rectifier KW - sr-load KW - ventricular-myocytes AU - Varro, A AU - Negretti, N AU - Hester, SB AU - Eisner, DA PY - 1993/04/01/ UR - http://dx.doi.org/10.1007/BF00374975 ER -