Term
| neuromuscular (myoneural) junction |
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Definition
| is the synapse between a motor neuron and a muscle cell. NMJ’s have been studied as model systems for many years. |
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Term
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Definition
| vesicles filled with chemical messenger molecules |
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Term
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Definition
| the neurotransmitter used by all vertebrate motor neurons that innervate skeletal muscle and is released when the vesicles fuse with the presynaptic membrane and moves into the narrow space between the pre- and the post-synaptic cells called the synaptic cleft. |
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Term
| How neurotransmitters are terminated |
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Definition
Enzymes may destroy the neurotransmitter. For example, acetylcholine is rapidly broken down by acetylcholinesterase.
The neurotransmitter may diffuse away from the synaptic cleft. (Not too important)
The neurotransmitter may be taken back via active transport into the pre-synaptic cell for re-packaging.. |
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Term
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Definition
| Post-synaptic NT receptor also functions as a ligand-gated channel. The nicotinic acetylcholine receptor (at neuromuscular junction) is an ionotropic receptor |
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Term
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Definition
| : Receptor (often G-protein coupled) stimulates a second messenger cascade which then affects ligand-gated channels (muscarinic ACH receptor). |
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Term
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Definition
| induce changes in the postsynaptic cell (generally via second messenger cascades) that lead to changes in ion channels. These receptors are generally G protein-coupled receptors. |
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Term
| excitatory postsynaptic potential (EPSP) |
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Definition
| Neurotransmitters that depolarize the postsynaptic membrane are excitatory and bring about these. They are only few mV. |
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Term
| bring about an inhibitory postsynaptic potential (IPSP). |
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Definition
| Neurotransmitters that hyperpolarize the postsynaptic membrane are inhibitory and bring about one of these. |
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Term
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Definition
| adds up the simultaneous influences of synapses at different sites on the postsynaptic cell. |
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Term
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Definition
| adds up postsynaptic potentials generated at the same site in a rapid sequence. |
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Term
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Definition
| The two neurons are connected by membrane proteins called connexons that form a tunnel through which ions and small molecules can pass. |
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