Ca-induced inactivation is an important property of L-type voltage-gated Ca channels. However, the underlying mechanisms are not yet understood well. There is general agreement that calmodulin (CaM) binds, in a Ca-dependent manner, to C-terminal motifs LA and IQ of the pore-forming a1C-subunit and acts as a sensor that conveys Ca-induced inactivation. New data indicate that both Ca-induced inac...

Calmodulin (CaM), as well as other Ca binding motifs (i.e., EF hands), have been demonstrated to be Ca sensors for several ion channel types, usually resulting in an inactivation in a negative feedback manner. This provides a novel target for the regulation of such channels. We have designed peptides that interact with EF hands of CaM in a specific and productive manner. Here we have examined w...

In cardiac muscle Ca -induced Ca release (CICR) from the sarcoplasmic reticulum (SR) is initiated by Ca influx via L-type Ca channels. At present, the mechanisms underlying termination of SR Ca release, which are required to ensure stable excitation-contraction coupling cycles, are not precisely known. However, the same mechanism leading to refractoriness of SR Ca release could also be responsi...

Copello JA, Zima AV, Diaz-Sylvester PL, Fill M, Blatter LA. Ca entry-independent effects of L-type Ca channel modulators on Ca sparks in ventricular myocytes. Am J Physiol Cell Physiol 292: C2129–C2140, 2007. First published February 21, 2007; doi:10.1152/ajpcell.00437.2006.—During the cardiac action potential, Ca entry through dyhidropyridine receptor L-type Ca channels (DHPRs) activates ryano...