The secretion of classical and peptide cotransmitters from a single presynaptic neuron involves a synaptobrevin-like molecule.
It is not yet understood how the molecular mechanisms controlling the release of neuropeptides differ from those controlling the release of classical transmitters, mainly because there are few peptidergic synapses in which the environment at the presynaptic release sites can be manipulated. Using Aplysia californica neuron B2, which synthesizes both peptide and classical transmitters, we have established two synaptic types. When B2 is cocultured with a sensory neuron, a peptidergic synapse is formed. In contrast, when B2 is cocultured with neuron B6, a classical synapse is formed. In contrast to a common assumption, single action potentials can release both types of transmitters. The secretion of peptide and classical transmitters by B2 is inhibited by the presynaptic injection of tetanus toxin, but not by an inactive mutant. Thus a synaptobrevin-like molecule is involved in the secretion of these two types of transmitters.
Whim
M D
MD
Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06520-8066, USA.
Niemann
H
H
Kaczmarek
L K
LK
D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D001048:Aplysia; D002118:Calcium / Q000494:pharmacology; D002478:Cells, Cultured; D018920:Coculture Techniques; D004553:Electric Conductivity; D017952:Ganglia, Invertebrate / Q000502:physiology*; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D008565:Membrane Proteins / Q000502:physiology*; D009419:Nerve Tissue Proteins / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D009475:Neurons, Afferent / Q000187:drug effects / Q000502:physiology*; D009479:Neuropeptides / Q000502:physiology*; D018408:Patch-Clamp Techniques; D017729:Presynaptic Terminals / Q000502:physiology*; D050683:R-SNARE Proteins; D011994:Recombinant Proteins / Q000494:pharmacology; D013569:Synapses / Q000187:drug effects / Q000502:physiology*; D013744:Tetanus Toxin / Q000494:pharmacology
D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; D050683:R-SNARE Proteins; D011994:Recombinant Proteins; D013744:Tetanus Toxin; D008274:Magnesium; D000109:Acetylcholine; D002118:Calcium