Posted by Jonathan on April 4, 2002, at 19:47:40
In reply to Kramer: question about neurons and transmitters, posted by Janelle on April 3, 2002, at 14:27:19
Hi Janelle -
"... does each neuron ONLY handle one kind of neurotransmitter (eg. a serotonin neuron only handles serotonin, a dopamine neuron only handles dopamine) OR does each neuron handle multiple neurotransmitters?"
Until recently, the answer to your question would have been "It depends what you mean by HANDLE":
• "handle" = "respond to", as a post-synaptic neuron receiving messages from other neurons - I think this is what Dr Kramer assumed you meant -
• or "handle" = "release", as a presynaptic neuron passing on its message to other neurons.
The latter, which we might call "Janelle's Hypothesis" if Sir Henry Dale hadn't thought of it first (in 1935), was believed for a long time to be correct and is the tacit assumption behind terms like "serotonergic neuron" (a neuron which is assumed to release ONLY serotonin from all of its presynaptic terminals). There's a superb review article about exceptions to Dale's Hypothesis available online - http://www.columbia.edu/~ds43/Sulzer_AminoAcidsrev.pdf - and a more advanced research paper by the same author, David Sulzer at Columbia University, New York, which includes some great pictures of real neurons - http://www.columbia.edu/~ds43/Sulzer_glutamateDA.pdf .
Please keep those questions coming :)
Jonathan.
poster:Jonathan
thread:101695
URL: http://www.dr-bob.org/babble/20020402/msgs/101852.html