A small number of open Ca2+ channels trigger transmitter release at a central GABAergic synapse.
To determine the number of open Ca(2+) channels necessary for transmitter release at the inhibitory basket cell-granule cell synapse in rat hippocampus, we combined presynaptic Ca(2+) imaging, recording of postsynaptic currents and modeling. We found that that the opening of three or fewer Ca(2+) channels triggered transmitter release. Furthermore, a small number of Ca(2+) channels were able to evoke release with high temporal precision, despite stochastic Ca(2+) channel opening.
Bucurenciu
Iancu
I
Institute of Physiology I, Universität Freiburg, Freiburg, Germany.
Bischofberger
Josef
J
Jonas
Peter
P
D000818:Animals; D000831:Animals, Newborn; D002118:Calcium / Q000378:metabolism; D002121:Calcium Channel Blockers / Q000494:pharmacology; D015220:Calcium Channels / Q000502:physiology*; D020864:Calcium Channels, N-Type / Q000502:physiology*; D002614:Chelating Agents / Q000494:pharmacology; D004533:Egtazic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D005089:Exocytosis / Q000187:drug effects / Q000502:physiology; D006624:Hippocampus / Q000166:cytology; D066298:In Vitro Techniques; D053444:Inhibitory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology; D015640:Ion Channel Gating / Q000187:drug effects / Q000502:physiology; D008959:Models, Neurological; D009474:Neurons / Q000166:cytology*; D018377:Neurotransmitter Agents / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D017729:Presynaptic Terminals / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D013269:Stochastic Processes; D013569:Synapses / Q000187:drug effects / Q000502:physiology; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*; D020867:omega-Agatoxin IVA / Q000494:pharmacology
D002121:Calcium Channel Blockers; D015220:Calcium Channels; D020864:Calcium Channels, N-Type; D002614:Chelating Agents; D018377:Neurotransmitter Agents; D020867:omega-Agatoxin IVA; D004533:Egtazic Acid; D005680:gamma-Aminobutyric Acid; C025603:1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid; D002118:Calcium