PHSL232 Lecture Notes - Lecture 3: Voltage-Dependent Calcium Channel, Calcium Atpase, Troponin C
Document Summary
The process and the responsible cellular structures involved in the calcium handling within the cardiomyocytes. Electro-mechanical interaction leading to excitation-contraction coupling, process of excitation-contraction coupling, and physiological consequences of the calcium plateau phase in the ventricular cell. Sa nodes depolarise spontaneously propagation of depolarisation wave along specific pathways. Reaches muscle; propagates further, made easy by gap junctions in intercalated discs. Electrical signal via ions will be transposed into a mechanical activity: overlap in time. Repolarisation decrease of ca2+ relaxation. L-type ca2+ channels open calcium enters the cell from the. Ecf: entering ca2+ ions trigger release of ca2+ from intracellular stores in the sr (via the ryanodine receptor (ryr)) Nb: there is a higher concentration of calcium both in the. 1microm, sr 1mm: l-type calcium channels are responsible for the release of. 25% of calcium entry into the cell, while the other 75% comes through ryr from the sr: this keeps the membrane potential higher.
