Lecture 16 + 17 Flashcards
What types of neurons should be mapped if examining excitatory nervous system circuits? (2)
Glutamatergic and cholinergic
What types of neurons should be mapped if examining inhibitory nervous system circuits? (2)
GABAergic and glycinergic
What is the Allan mouse brain atlas?
Genome-wide atlas of gene expression in mouse brain created using in situ hybridization
What is the role of ACh in neuromuscular junctions?
Generation of post-synaptic depolarization activates pentameric ionotropic cys-loop channels
Cholinergic neuron gene marker
Choline acetyltransferase (ChAT)
Where is ACh secreted from in the CNS?
Axonal swellings (varicosities)
Define volume transmission
Axonal swelling secretion and diffusion of neurotransmitters into extracellular environment
What function do pre-synaptic nAChR’s have?
Boost neurotransmission
AMPA/Kainate receptor blocker
CNQX
What is a muscarinic receptor?
Receptor which can be activated by fungal toxin muscarine
What is the role of the G_q -> phospholipase C (PLC) -> protein kinase C (PKC) pathway?
Drives post-synaptic excitation in hippocampus through increased cytoplasmic Ca2+ and PKC activation
mAChR activation leads to inhibition of what K+ channels? (2)
M-type K_v channels
Ca2+ activated SK channels
How do M1/M3 mAChRs inhibit M-type K_v channels?
PIP2 is required for M-type K_v channel activity. mAChR activation results in decrease in PIP2.
What is the effect of M1/M3 mAChR activation on pyramidal neurons?
Increased excitability
What two neurological functions are pyramidal neurons important for?
Attention and memory formation
How can volume transmittion of ACh cause pre- and post-synaptic inhibitory effects?
M2/M4 mAChRs inhibit pre-synaptic Ca2+ channels and activate post-synaptic K+ channels
M2/M4 mAChR blocker
Atropine
What are the effects of atropine? (2)
- M2/M4 blocking
2. Enhanced ACh secretion in cerebral cortex
Why does atropine result in increased ACh secretion?
- Attenuated M2/M4 mAChRs
- Loss of active G_O complex
- Loss of pre-synaptic Ca_v2 channel inhibition
What do cholinergic pathways in the brain modulate?
Neural circuits involved in attention and memory formation
Degeneration of what neurons are associated with Alzheimer’s disease?
Cholinergic neurons
List 3 iGluRs
- NMDA receptors
- AMPA receptors
- Kainate receptors