Role of Na-Ca Exchange in Neonatal and Adult Ventricular Cells: A Simulation Study
نویسندگان
چکیده
The Na-Ca exchange assumes considerable importance in neonatal cells with a morphologically sparse sarcoplasmic reticulum. Our simulation shows that the neonatal ventricular cell consumed larger amount of ATP than the adult ventricular cell, owing to a long relaxation time. The amount of ATP consumed per beat was reduced to the amount equivalent to the adult ventricular cells, thus increasing the relative current density of Na-Ca exchange by 4-fold, which is consistent with the observed current density in the neonatal rabbit ventricular cells.
منابع مشابه
Na /Ca exchange activity in neonatal rabbit ventricular myocytes
Huang, Jingbo, Leif Hove-Madsen, and Glen F. Tibbits. Na / Ca exchange activity in neonatal rabbit ventricular myocytes. Am J Physiol Cell Physiol 288: C195–C203, 2005. First published August 16, 2004; doi:10.1152/ajpcell.00183.2004.—Much less is known about the contributions of the Na /Ca exchanger (NCX) and sarcoplasmic reticulum (SR) Ca pump to cell relaxation in neonatal compared with adult...
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