Blood Calcium Levels in Immature Rats: Influence of Extracellular Calcium Concentration on Myocardial Calcium Handling

Abstract

Abstract:Calcium ions play an important role in several cell functions, from fertilization to cell death. from 1.2 to 2 mM, which also increased the Ca 2+ content in the sarcoplasmic reticulum (SR), and changed the pattern of competition between the main transporters that remove Ca 2+ from the cytosol (SR Ca 2+ -ATPase and Na + /Ca 2+ exchanger). These observations stress the importance of using physiological [Ca 2+ ] o values for reliability of results. It is expected that the present calcemia data, reported for the first time in immature rats, may contribute to the refinement of in vitro experiments with neonatal rat preparations.

Estimation of the fractional sarcoplasmic reticulum Ca2+ release in intact cardiomyocytes using integrated Ca2+ fluxes

“…Estimation of these fluxes has been used to assess the relative contribution of these transporters for twitch relaxation in several conditions Li et al 1997;Bassani and Bassani 2002;Piacentino et al 2003;Carvalho et al 2006;Curran et al 2007), as well as for the estimation of SERCA-mediated Ca 2+ flux during spontaneous Ca 2+ release (MacQuaide et al 2007) and of SERCA empirical kinetic parameters in intact cells (Picht et al 2007;Bassani et al 2012 Berlin et al 1994;Bassani et al 1998;Trafford et al 1999), provided that the signal of the Ca 2+ indicator is properly calibrated. FR is an important parameter for assessment of the efficiency of excitation-contraction coupling, as most of the Ca 2+ pool available for myofilament activation is released from the SR in the adult mammalian heart.…”