Synaptic Transmission Part II

(6 pages)
Previewing pages 1, 2 of actual document.

Synaptic Transmission Part II

Lecture number:
Lecture Note
University of Southern California
Bisc 307l - General Physiology
Documents in this Packet

Unformatted text preview:

BISC 307L 1st Edition Lecture 7 Current Lecture Synaptic Transmission Continued  Steps in Chemical Synaptic Transmission o 1. Synthesis  synthesis of transmitter from precursor (enzymatic synthesis)  enzymes needed are made in the cell body of the neuron because only in the cell body are there organelles responsible for protein synthesis  travel along using axoplasmic transport  presynaptic terminal  usually local, one exception is the peptide transmitters which are made in the cell body o 2. Storage  in vesicles  packaged into these vesicles using active transport  neurotransmitters highly concentrated in the vesicles o 3. Release  across synapse  when action potential comes down the axon and invades the terminal o 4. Receptor interaction  1. ionotropic  neurotransmitter affects ion channels and causes current flow in postsynaptic cell  2. metabotropic  neurotransmitter ahs metabolic affect on postsynaptic cell  regeneration of second messengers  Paracrine signaling and endocrine signaling are common with chemical synapses o 5. Inactivation  getting rid of the neurotransmitter  3 mechanisms: Fate of neurotransmitter  1. Hydrolysis by a specific enzyme either on the postsynaptic membrane or on the presynaptic membrane or in the synaptic cleft (neuromuscular junction)  Acetylcholine in neuromuscular junction  2. Diffusing out of the synaptic cleft (taken up by glial cells or just diffuse away)  3. Reuptake by secondary active transporters back into the synaptic terminal

View Full Document

Access the best Study Guides, Lecture Notes and Practice Exams