neurophysiology Flashcards
Which neurotransmitter system is a major inhibitory
a. Acetycholine (Cholinergic system)
b. Glutamate (Glutamatergic system)
c. GABA (GABAergic system)
c. GABA (GABAergic system)
ACh
- Released by:
- Receptor:
– Somatic motor neurons
– Nicotinic
Nicotinic receptors are actually permeable to ________
So their reversal potential is a mixture of the 2
both Na+ and K+
Acetylcholine lifecycle
After ACh done with work it is degraded by AChE which CANNOT be reabsorbed by the presynaptic end.
It first lysed to Choline and acetic acid
Choline is transported back via Choline transporter.
Choline + Acetyl CoA = ACh
Acetylcholine: a neuromodulator
* Released by:
Projection:
Function:
Receptors:
- Released by:
– Neurons in the basal forebrain - Projection:
– Cerebral Cortex
and hippocampus - Function:
– Arousal and wakefulness
– Aspects of learning and memory - Receptors:
– Nicotinic and Muscarinic
Alzheimer’s Disease
Cholinergic neurons in
the basal forebrain are
some of the first
neurons to die
– Management:
acetylcholinesterase
inhibitors help a bit.
Which neurotransmiter system is the major excitatory in the BRAIN?
Glutamate
Which receptors are important for Learning and memory
Ie NMDA receptors only open
when the cell is already
depolarised
* NMDA receptors are
permeable to Ca2+
* Ca2+ can activate enzymes / 2nd
messengers
What strengthen the synapse in the NMDAR activation?
NMDAR activation and Ca2+ influx can
cause strengthening of the syanpse
Ie future EPSPs will be bigger
LTP induction mechanism
3 LTP mechanisms responsible for strengthening the connection / enlarging EPSPs /
increasing conductance at the glutamatergic synapse:
1) Insertion of new AMPA receptors
2) Phosphorylation of AMPA receptors
3) Enhancement of neurotransmitter release (ie increase probability of release)
GABA
* Receptors typically lead to
____ ion influx
* Hyperpolarization (
chloride