MCDB 351 Final: FinalExamSynapse

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Document Summary

Early synaptic contacts don"t exhibit pre or postsynaptic specializations. Presynaptic neuron capable of releasing neurotransmitter before establishment of synapse. Shortly following contact of motor growth cone with muscle, postsynaptic currents are enhanced. Suggests that a retrograde signal from the postsynaptic muscle promotes transmitter release by the presynaptic motor neuron. Alternatively, contact might initiate increase in achrs in postsynaptic muscle. Following contact between pre and postsynaptic neurons the presynaptic specializations appear prior. Removal of motor neurons leads to abnormal distribution of achrs. Signal from presynaptic motor neuron regulates differentiation of postsynaptic specializations in muscle. Motor nerve regenerates and establishes synaptic contact at site of the original nmj. Psd-95 large protein found at postsynaptic membrane and closely related to neurotransmitter receptors. In culture presynaptic specialization occur before postsynaptic specialization. What happens in culture not necessarily what happens in animal. 1:1 synapse simple synapse and it"s the muscle which are recording form.