L22 Flashcards
1
Q
explain neurodegeneration, what illnesses its linked to, and how it could be controlled
A
- Resulting from excessive glutamate/ Ca+
- NMDA receptors involved
- Linked to
○ Ischemia
○ Traumatic brain injuries
○ Alzheimer’s disease
○ MNDS - Controlling it
○ Retard neuronal death in the affected areas
Glutamate receptor antagonists + inhibitors downstream of receptor activation
2
Q
explain alzheimers disease
A
- Cholinergic (means uses Ach as neurotransmitter) neurons in basal forebrain nucleus + hippocampus degenerate
- Cholinergic terminals in cortex lost
- (obvious solution is the increase Ach neurotransmitters in brain, used before, doesn’t work)
- Brain shrinks- plaques + tangles block communication between brain cells
- Progressively lose memory + cognitive function
- Inability to carry out activities + daily living
- Acetylcholinesterase inhibitors + memantine (is a NMDA receptor antagonist, stops glutamate from binding, stopping Ca+ entering) the only drugs approved for treating Alzheimer’s disease
3
Q
define plaques and intraneuronal
A
○ Plaques
§ Extracellular morphous extracellular deposits of beta amyloid protein
○ Intraneuronal
neurofibrillary tangles, comprising filaments of a phosphorylated form of microtubule associated protein
4
Q
explain cholinergic neurons
A
- Neurons that use Ach as neurotransmitter
- Found in brain
- Control cognitive, arousal, memory, motor control, learning
In peripheral, involved with voluntary control of movement + autonomic nervous system
5
Q
explain the breakdown of acetylcholine
A
- Ach broken down to acetate + choline by Ach esterase, so choline recycled
6
Q
explain the poisoning via acetylcholinesterase inhibitor
A
- Leads to accumulation of Ach in the synaptic cleft, resulting in over stimulation of nicotine + muscarinic Ach receptors and impeded neurotransmission
Typical symptoms are agitation, muscle weakness, hypersalivation, sweating
7
Q
explain ALS
A
- Most common motor neuron disease is ALS (amyotrophic lateral sclerosis)
○ More common in males
○ Appears after 50yrs
○ Affects both upper + lower motor neurons
§ Neurons in brain + spinal cord
§ Which affect muscles of arms, legs, mouth, respiratory system
§ Symptoms- weight loss, slurred speech, difficulty breathing
Patients live for 3-5yrs after diagnosis, with care could be 10+ yrs
8
Q
explain the motor response from the LMN
A
- Provides input to lower motor neurons
1. Local circuit neurons
2. Upper motor neurons
3. Basal nuclei neurons
Cerebellar neurons