Wang Haitao

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• Wang Haitao

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Research area Voltage-gated Na channels are
responsible for initiation of electrical
signaling in nerve, muscle and other excitable
cells, and voltage-gated Ca channels are
responsible for initiation of synaptic
transmission in neurons, excitation-contraction
in muscle, secretion in endocrine cells, and many
other processes.
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Ca palys important role in trigger presynaptic
transmitter release
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Ca2.1, (P/Q type Ca channel)
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Methods

• Cultured SCG(superior cervical ganglion )neuron
• form fast cholinergic synaptic transmission
  between them
• cDNAs transfection to exogenous express WT or
  Mutant P/Q type Calcium channels in SCG
• Whole cell recording
• Sharp electrode intracellular reocording

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P/Q-Type Ca2 Currents in SCG Neurons
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Calcium Dependent Facilitation and Inactivation
of CaV2.1 Channels
EPSP k(ICa)n
k 1 ,n 3.5
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PPF and PPD Mediated by CaV2.1 Channels
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PPF and PPD Mediated by CaV2.1 Channels
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Plasticity of Synaptic Transmission Mediated by
CaV2.1 Channels during Bursts of Neuronal
Activity
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Augmentation and PTP Mediated by CaV2.1 Channels
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Summary

• A mutation of the Iq-like motif in the C
  terminus that blocks Ca2/CaS dependent
  facilitation of the P/Q-type Ca2 current
  markedly reduces facilitation of synaptic
  transmission.
• Deletion of the nearby calmodulin-binding
  domain,which inhibits CaS-dependent
  inactivation,substantially reduces depression of
  synaptic transmission.
• Residual Ca2 in presynaptic terminals can act
  through CaS dependent regulation of CaV2.1
  channels to induce short-term synaptic
  facilitation and rapid synaptic depression.
  Activity-dependent regulation of presynaptic
  CaV2.1 channels by CaS proteins may therefore be
  a primary determinant of short-term synaptic
  plasticity and information-processing