Transmitter release increases intracellular calcium in perisynaptic Schwann cells in situ

Neuron. 1992 Jun;8(6):1069-77. doi: 10.1016/0896-6273(92)90128-z.


Glial cells isolated from the nervous system are sensitive to neurotransmitters and may therefore be involved in synaptic transmission. The sensitivity of individual perisynaptic Schwann cells to activity of a single synapse was investigated, in situ, at the frog neuromuscular junction by monitoring changes in intracellular Ca2+ in the Schwann cells. Motor nerve stimulation induced an increase in intracellular Ca2+ in these Schwann cells; this increase was greatly reduced when transmitter release was blocked. Furthermore, local application of the cotransmitters acetylcholine and ATP evoked Ca2+ responses even in the absence of extracellular Ca2+. Successive trains of nerve stimuli or applications of transmitters resulted in progressively smaller Ca2+ responses. We conclude that transmitter released during synaptic activity can evoke release of intracellular Ca2+ in perisynaptic Schwann cells. This Ca2+ signal may play a role in the maintenance or modulation of a synapse. These data show that synaptic transmission involves three cellular components with both postsynaptic and glial components responding to transmitter secretion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium / metabolism*
  • Electric Stimulation
  • Intracellular Membranes / metabolism*
  • Neuromuscular Junction / metabolism
  • Neuromuscular Junction / physiology
  • Neurotransmitter Agents / metabolism*
  • Neurotransmitter Agents / physiology
  • Rana pipiens
  • Schwann Cells / metabolism*
  • Synapses / physiology*


  • Neurotransmitter Agents
  • Calcium