E.4a Neurotransmitters & Synapses
26/01/2014 § Leave a comment
Hey, Mr. Ferguson, what did one cell say to his sister cell when she stepped on his toe?
Okay, let’s do this. Assessment statement number 2 tells us to explain how decision-making in the CNS can result from the interaction between the activities of excitatory and inhibitory neurons at synapses. The CNS is the central nervous system that holds the sites where decision-making occurs. Action potentials in a neuron’s post-synaptic membrane (as a result of input from the pre-synpatic neurons) are the cause of excitatory and inhibitory activities. I think.
EPSPs are excitatory post-synaptic potentials, which obviously start through excitatory neurotransmitters. From what I understand, there are specific receptor proteins for these excitatory neurotransmitters, such as epinephrine, dopamine, and serotanin. When the neurotransmitter binds to the receptor protein, the result is a post-synaptic membrane that is permeable to sodium, which can then move across the membrane, depolarising it for enzyme to catabolise the neurotransmitters (an example of which is monoamine oxidase catabolising norepinephrine).
IPSPs are just the opposite; inhibitory post-synpatic potentials that root from inhibitory transmitters, like glycine, gamma-aminubutyric acid (GABA) and acetylcholine. When the neurotransmitter binds to the receptor proteins (which are specific for those inhibitory neurotransmitters), the result is a post-synaptic membrane that is less permeable to sodium. This allows potassium to diffuse across the post-synaptic membrane and hyperpolarise it.