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A Level Biology Help ! Synaptic inhibition Watch

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    Hello!
    I am currently doing a paper on nervous system and there is a question about synaptic inhibition. I need to define it and its functions. I am really struggling to find any information on the subject, can anyone point me to the right direction? I know it is also called IPSP.
    Thanks in advance !
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    IPSP = Inhibitory Post-Synaptic Potential

    Basically, when a nerve impulse arrives at the synaptic knob (the end of the axon away from the cell body of a neurone (nerve cell)), a neurotransmitter is released, i.e. a chemical substance e.g. acetylcholine (ACh) OR norepinephrine (NE). This diffuses across the synaptic cleft (the gap between the synaptic knob and the cell body of the next neurone [or of muscle cell [myocyte]) and acts on receptors on the second neurone (called the post-synaptic neurone [post = after]). Here the chemical can either stimulate the 2nd neurone (by acting on receptors on its surface), or can inhibit it.

    An inhibitory effect would be produced by hyperpolarization of the neuronal membrane, so that it is more difficult than normal for the neurone to "fire". This is the IPSP and is created by more Na+ (sodium ions) leaving the neurone, so that the electrical potential inside the cell is more negative than the usual -70mV (millivolts).

    Hope this makes it more easy to understand.
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    (Original post by macpatelgh)
    IPSP = Inhibitory Post-Synaptic Potential

    Basically, when a nerve impulse arrives at the synaptic knob (the end of the axon away from the cell body of a neurone (nerve cell)), a neurotransmitter is released, i.e. a chemical substance e.g. acetylcholine (ACh) OR norepinephrine (NE). This diffuses across the synaptic cleft (the gap between the synaptic knob and the cell body of the next neurone [or of muscle cell [myocyte]) and acts on receptors on the second neurone (called the post-synaptic neurone [post = after]). Here the chemical can either stimulate the 2nd neurone (by acting on receptors on its surface), or can inhibit it.

    An inhibitory effect would be produced by hyperpolarization of the neuronal membrane, so that it is more difficult than normal for the neurone to "fire". This is the IPSP and is created by more Na+ (sodium ions) leaving the neurone, so that the electrical potential inside the cell is more negative than the usual -70mV (millivolts).

    Hope this makes it more easy to understand.
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    (Original post by alisaalisa)
    Hello!
    I am currently doing a paper on nervous system and there is a question about synaptic inhibition. I need to define it and its functions. I am really struggling to find any information on the subject, can anyone point me to the right direction? I know it is also called IPSP.
    Thanks in advance !
    Well, if you're going down the IPSP route then yh, the basic principal as has already been said is that you hyperpolarise the post-synaptic neurone (usually by opening a ligand-gated chloride channel) so that it's harder to reach the threshold needed to kick off an action potential. However, synapses can be inhibited in other ways, namely by receptor antagonists. A classic example would be atropine, which is a mAChR antagonist. But yh, the question probably wasn't about that!
 
 
 
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