Inhibition of CaV2.3 channels by NK1 receptors is sensitive to membrane cholesterol but insensitive to caveolin-1

Pflugers Arch. 2015 Aug;467(8):1699-709. doi: 10.1007/s00424-014-1605-0. Epub 2014 Sep 11.


Voltage-gated, CaV2.3 calcium channels and neurokinin-1 (NK1) receptors are both present in nuclei of the central nervous system. When transiently coexpressed in human embryonic kidney (HEK) 293 cells, CaV2.3 is primarily inhibited during strong, agonist-dependent activation of NK1 receptors. NK1 receptors localize to plasma membrane rafts, and their modulation by Gq/11 protein-coupled signaling is sensitive to plasma membrane cholesterol. Here, we show that inhibition of CaV2.3 by NK1 receptors is attenuated following methyl-β-cyclodextrin (MBCD)-mediated depletion of membrane cholesterol. By contrast, inhibition of CaV2.3 was unaffected by intracellular diffusion of caveolin-1 scaffolding peptide or by overexpression of caveolin-1. Interestingly, MΒCD treatment had no effect on the macroscopic biophysical properties of CaV2.3, though it significantly decreased whole-cell membrane capacitance. Our data indicate that (1) cholesterol supports at least one component of the NK1 receptor-linked signaling pathway that inhibits CaV2.3 and (2) caveolin-1 is dispensable within this pathway. Our findings suggest that NK1 receptors reside within non-caveolar membrane rafts and that CaV2.3 resides nearby but outside the rafts. Raft-dependent modulation of CaV2.3 could be important in the physiological and pathophysiological processes in which these channels participate, including neuronal excitability, synaptic plasticity, epilepsy, and chronic pain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium Channels, R-Type / genetics
  • Calcium Channels, R-Type / metabolism*
  • Caveolin 1 / genetics
  • Caveolin 1 / metabolism*
  • Cholesterol / metabolism*
  • HEK293 Cells
  • Humans
  • Membrane Microdomains / drug effects
  • Membrane Microdomains / metabolism*
  • Membrane Potentials
  • Rabbits
  • Rats
  • Receptor Cross-Talk*
  • Receptors, Neurokinin-1 / genetics
  • Receptors, Neurokinin-1 / metabolism*
  • Transfection
  • beta-Cyclodextrins / pharmacology


  • Calcium Channels, R-Type
  • Cav1 protein, rat
  • Caveolin 1
  • Receptors, Neurokinin-1
  • beta-Cyclodextrins
  • methyl-beta-cyclodextrin
  • Cholesterol