Calcium channels in neuronal excitability

Principal Investigator: Ľubica Lacinová
Coordinating Organization: Institute of Molecular Physiology and Genetics SAS, Bratislava, Slovak Republic

Duration: May 2011 – October 2014


Voltage-gated Ca2+ channels (VGCCs) mediate influx of Ca2+ ion, which controls a number of processes including neuronal development and plasticity. L-type voltage-gated Ca2+ channels represent a well-established therapeutic target. Known L-VGCC isoforms (Cav1.2, Cav1.3 and Cav1.4) possess different biophysical properties, thus differentially affecting the dynamics of Ca2+ influx and electrical excitability. This raises a question, to which extent these isoforms contribute to various cellular functions. We will use two established models of neurogenesis: PC12 cell line and primary culture of hippocampal neurons. To analyze role of specific subtypes of L-VGCC we will use method of gene silencing. First we shall optimize cell transfection by siRNA and analyze alteration of structure and function of cell membrane. To assess contribution of Cav1.2 and/or Cav1.3 channels to cellular excitability we will employ whole cell patch clamp measurements. Activity of L-VGCC is in direct relation with activity of other surface transport proteins like Na-Ca-exchanger or Na-K-ATPaze and with activity of intracellular calcium channels like IP3 receptors. We will analyze possible alterations in their expression by PCR method. Altered ratio of transport proteins may affect cell architecture. We will use electron microscopy to assess changes in cell ultrastructure.