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Updated: Aug 8, 2026
13:28
Automated Detection and Analysis of Exocytosis
Published on: September 11, 2021
T-type channels-secretion coupling: evidence for a fast low-threshold exocytosis
E Carbone1, A Marcantoni, A Giancippoli
1Department of Neuroscience, NIS Center of Excellence, CNISM Research Unit, Torino, 10125, Italy. emilio.carbone@unito.it
Pflugers Archiv : European Journal of Physiology
|June 8, 2006
Summary
Transient low-voltage-activated (LVA) Ca2+ channels, or T-type channels, are increasingly recognized for their role in fast transmitter release. This review highlights their unique participation in fast exocytosis and control of Ca2+-dependent processes.
Area of Science:
- Neuroscience
- Cell Biology
- Molecular Biology
Background:
- T-type channels are low-voltage-activated (LVA) Ca2+ channels crucial for Ca2+ entry in excitable cells.
- Their roles in cell excitability, muscle contraction, and hormone release are well-established.
- Traditionally, high-voltage-activated (HVA) Ca2+ channels were thought to mediate transmitter release.
Purpose of the Study:
- To review emerging evidence for T-type channels in fast transmitter release.
- To discuss the specific mechanisms and Ca2+-dependent processes regulated by T-type channels in exocytosis.
- To highlight the unique contribution of T-type channels to synaptic function.
Main Methods:
- Literature review of studies on T-type channel function in various tissues and cell types.
- Analysis of data from reciprocal synapses, neuronal contacts, and neuroendocrine cells.
- Examination of evidence from recombinant alpha(1) channel subunit transfections.
Main Results:
- Accumulating evidence supports a role for T-type channels in fast transmitter release.
- T-type channels are implicated in synaptic transmission in the retina, olfactory bulb, and nociceptive pathways.
- They regulate large dense-core vesicle release in neuroendocrine cells, comparable to HVA channels.
Conclusions:
- T-type channels can trigger fast, low-threshold secretion when properly localized.
- They play a specific role in fast exocytosis, distinct from traditional HVA channel functions.
- Further research is warranted to understand their involvement in vesicle depletion and recycling during exocytosis.
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