BIOL 3402 Lecture Notes - Lecture 14: Chloride Channel, Signal Transduction, Axon Terminal
Document Summary
Nerve signal can go no further once it reaches the end of axon: triggers release of neurotransmitter, stimulates new wave of activity. Synapse between 2 neurons: 1st neuron is the presynaptic neuron (axondendritic, axosomatic, axoaxonic) Releases neurotransmitter: 2nd neuron is postsynaptic neuron. In cerebellum, 1 neuron can have 100,000 synapses! Chemical synapses: neurons communicate by releasing chemicals: acetylcholine first discovered neurotransmitter. Electrical synapses: fast, but can"t integrate info: uses gap junctions. Synaptic know of presynaptic neuron contains synaptic vesicles containing neurotransmitter. Each neuron (usually) carries one specific neurotransmitter. Acetylcholine: unique, formed from acetic acid and choline. Excitatory cholinergic synapse: uses ach, voltage-gated ca channels. Neurotransmitter diffuses across synaptic cleft and binds to receptors. Binding of neurotransmitter to receptor activates signal transduction pathways. Inhibitory gaba synapse: uses y-aminobutyric acid, chloride channel (cl enters making it - , postsynaptic neuron inhibited, won"t fire. Excitatory adrenergic synapse: uses norepinephrine (adrenaline) Can manage hypertension: uses enzyme receptors (g proteins, turns genes on .
