PHGY 209 Lecture Notes - Lecture 2: Excitotoxicity, Synaptic Plasticity, Excitatory Postsynaptic Potential

• School: McGill University
• Department: Physiology
• Course: PHGY 209
• Professor: Ann Wechsler

Document Summary

Synaptic vesicles and calcium channels are localized to the presynaptic terminal by a complex of proteins that regulates vesicle fusion: one of the proteins is the calcium-binding protein (synaptotagmin) Calcium triggers a process that releases the vesicle. Botox is taken up by presynaptic terminals which activate muscle cells and renders them non- functional o black widow spider venom triggers uncontrolled release of neurotransmitter. The postsynaptic response to neurotransmitter is either an excitatory postsynaptic potential (epsp) which depolarizes the postsynaptic membrane, or an inhibitory postsynaptic potential (ipsp), which hyperpolarizes the postsynaptic membrane. The inhibitory synapse uses a neurotransmitter called gaba. The main excitatory neurotransmitter in the brain is glutamate: glutamate is an amino acid and a major neurotransmitter. Rapid excitatory transmission at synapses is primarily due to the actions of glutamate on two types of ionotropic glutamate receptors: ampa receptors, nmda receptors. Both receptors are found in the postsynaptic spine. Ampa receptors and nmda receptors are examples of ionotropic receptors.