N-type and L-type Calcium Channels Are Present in Nerve Growth Cones. Numbers Increase on Synaptogenesis

Brain Res Dev Brain Res. 1991 Jun 21;60(2):197-203. doi: 10.1016/0165-3806(91)90048-n.


We have demonstrated the presence of both N- and L-type calcium channels in growth cone and other subcellular fractions of fetal rat brain, using the ligands omega-conotoxin GVIA for N-type channels and nitrendipine for L-type channels. The N-type channels seem to be distributed evenly throughout the perikaryon, neurite shaft and growing tip of the neurons. In contrast, the L-type channels appear to have a lower density in the growth cone than on the rest of the neuron. These observations apply at least within the limitations of cell fractionation technology. We have also studied both calcium channel subtypes in rat brain synaptosomal membranes. In both adult and fetal fractions there are approximately 6 times more N-type than L-type channels. Synaptosomal membranes contain more N- and L-type channels than any of the fetal subfractions, indicating that there is a substantial increase in calcium channel numbers upon synaptogenesis.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Brain / embryology*
  • Brain / physiology
  • Calcium Channels / metabolism
  • Calcium Channels / physiology*
  • Cerebral Cortex / physiology*
  • Fetus
  • Gestational Age
  • Kinetics
  • Nitrendipine / metabolism*
  • Peptides, Cyclic / metabolism*
  • Rats
  • Synapses / physiology*
  • omega-Conotoxin GVIA


  • Calcium Channels
  • Peptides, Cyclic
  • omega-Conotoxin GVIA
  • Nitrendipine