Please enable JavaScript.

Coggle requires JavaScript to display documents.

Synaptic Transmission I (Chemical Synapse (Neurotransmitters (peptides…

- - - - asymmetric
      - round vesicles
      - excitatory
    - - symmetric
      - flattened vesicles
      - inhibitory
  - - - synthesis occurs in axon terminal
      - stored in synaptic vesicles
    - - synthesis occurs in axon terminal
      - stored in synaptic vesicles
    - - large proteins formed in rough ER
      - in golgi – large precursor protein cleaved
      - active peptide = packaged into secretory granule for transport & release
    - - i.e. ACh
        
        nicotinic AChR: ACh @ neuromuscular junction produces excitation in postsynaptic cell
        
        muscarinic AChR: ACh at heart leads inhibition in postsynaptic cell
    - - each contains 1 quantum of transmitter
    - - Reuptake – neurotransmitter reenters presynaptic terminal
      - Diffusion – away from synapse
      - Enzymatic destruction – inside terminal cytosol/synaptic cleft
        
        AChE cleave ACh to inactive state
  - - - postsynaptic currents cause excitatory/inhibitory response
    - - synaptobrevin – vesicle membrane
      - SNAP-25 & syntaxin in plasma membrane
- - - - effector doesn't necessarily = effector
  - - - GABA-A receptor
        
        conducts Cl-
        
        flows into cell & keep Vm near -65 mV
        
        less likely that cell fires AP
        
        inhibitory synapse (IPSP)
      - Nicotinic ACh
      - AMPA-type Glu receptor
    - - channels that allow Na+ & K+ – reversal potential = 0mV
        
        Na inward & K+ outward = equilibrium
        
        no net current
        
        Ereversal = Vm above – outward & below – inward
        
        ligand-gated receptor often conduct more than 1 ion
        
        channel behaves as if conducts 1 ion whose Eion = Ereversal & each ion has own g
        
        i.e. AChR – gNa>gK & AMPA-glu
        
        channel would make it more likely for cell to fire AP (ESPS)
        
        channel works hard to bring Vm to Ereversal
  - - - G-protein-gated ion channel
      - enzyme
        
        synthesizes 2nd messenger which = freely soluble
        
        1st messenger = neurotransmitter
    - - effect efficacy of ionotropic receptors
      - neuromodulatory
      - transmitters that bind this receptors = neuromodulators
- - - - inferior olive neurons: send climbing fiber input to cerebellum
      - synchronously activate purkinje cells
- - - - solution transferred to heart 2 & heart rate slowed + contraction strength weakened