Neuro Pharmacology

Question 1

Patho of epilepsy?

Answer 1

Tissues from an epileptic focus have less synaptic inhibition leading to cells becoming easily excitable increasing the firing rate and a subsequent seizure

Question 2

Adverse effects of midazolam?

Answer 2

Sedation, headache, blurred vision, hypotension, nausea/vomiting, respiratory depression.

Question 3

How does neuronal communication work?

Answer 3

traveling wave of electrical excitation known as an action potential that is orchestrated by the opening and closing of ion channels

Question 4

What is GABA?

Answer 4

inhibitory neuron that inhibits or slows down excitatory impulses

Question 5

Too little of what neuron can lead to seizures?

Answer 5

GABA

Question 6

Describe the MOA of Anti-Epileptic drugs, and the four ways they work.

Answer 6

MOA: lower neuronal excitability and enhance neuronal inhibition.
1- blocking of voltage gated sodium channel -> reduces NA in neuron
2- blocking of high and low voltage gated calcium channels
3- enhancing of GABA system
4- blocking of calcium channel and binding of SV2a protein

Question 7

Seizure pathology? How should the brain act normally?

Answer 7

Abnormal excessive synchronous electrical activity. Normally neuronal firing is regulated by a balance between inhibitory and excitatory synaptic input. Brain cells generate action potentials.

Question 8

What is the patho of status?

Answer 8

failure of mechanism to terminate a seizure either due to an increase in the excitatory mechanism or a decrease in the inhibitory mechanism.

Question 9

Whats important to note about a prolonged seizure?

Answer 9

Difficult to abort

Question 10

Treatable causes of seizure in the pre hospital field and their treatments?

Answer 10

Hypoglycemia - D10
Eclampsia - Magnesium

Question 11

What is the doze for Midaz in the Adult ACP World for seizures?

Answer 11

2-5mg IV/IO to effect, 5-10 mg IM titrate to effect, MAX DOSE 30 MG

Question 12

Describe the MOA of Midaz

Answer 12

Midaz increases the affinity for GABA to GABA binding sites, GABA binds to gaba-a receptors, increasing the frequency of anion channel opening (chorlide), influx of chloride rushes in bringing the cell negative and further hyperpolarizing the cell, this hyperpolarizing prolongs the depolarization phase and their ability to conduct action potentials quick thus increasing inhibition.

Question 13

What is a hypnotic used for?

Answer 13

used to initiate and maintain sleep

Question 14

What is an anxiolytic used for?

Answer 14

to treat acute anxiety

Question 15

How does midaz work in an anxious patient

Answer 15

It increases inhibition which inhibits the SNS which is firing the action potentials that is giving the feelings of fear and anxiousness, net result is increased calmness and decreased anxiety

Question 16

What do AMPA receptors permit entry of?

Answer 16

Sodium Ions

Question 17

What do NMDA receptors permit entry of?

Answer 17

Calcium Ions

Question 18

What does the gaba-a subunit a1 control?

Answer 18

Sleep

Question 19

What does the gaba-a subunits a2-a3 control?

Answer 19

Anxiety

Question 20

Where in the brain controls fear and anxiety?

Answer 20

Amygdala

Question 21

How does anxiety occur?

Answer 21

In times of stress excitatory neurons in the amygdala fire rapidly, sending excitatory signals to other parts of the brain.

Question 22

What regulates fear and anxiety?

Answer 22

Inhibitory neurons in the amygdala by releasing GABA and inhibiting the excitatory signals, GABA allows for the calming tranquilizing effect and prevents us from becoming overwhelmed in stressful situations.

Question 23

What is the difference between benzos and barbs

Answer 23

Benzos increase opening frequency of ion channels, barbs increase opening duration.

Question 24

What do barbiturates do?

Answer 24

Decrease activity of the excitatory neurotransmitters acetylcholine and glutamate.

Question 25

Adverse effects of barbs?

Answer 25

Dizzy, lightheaded, sedation, memory and attention deficits. Small OD can lead to coma and death due to respiratory depression

Question 26

Therapeutic uses for anxiolytics or hypnotics

Answer 26

1- anxiety and related conditions
2- sleep disorder
3- pre operative sedation and anxiety
4- etoh withdrawal
5- epilepsy and status
6- muscle spams

Question 27

What is important to note about the duration of midaz?

Answer 27

It is short acting

Question 28

What is important to note about benzos regarding CNS?

Answer 28

The greater the dose the more CNS depression you will have, due to decreased action potentials

Question 29

How does midaz affect the body ie hr rr etc?

Answer 29

Decreases HR thus decreases BP and decreases RR overall CNS depression

Question 30

How to hypnotic agents work?

Answer 30

agonists at gaba sites, gaba inhibits excitatory impulses allowing anxiety to stop and bringing calm to the patient

Question 31

What is glutamate?

Answer 31

Excitatory neuron

Question 32

How does a cell generate action potentials faster and cause a seizure?

Answer 32

Cell becomes +++ as voltage gated channels open along the ion which leads to propogation of depolarization down the axon = depol and generation of action potentials. Increased glutamate leads to increased activity of NMDA and AMPA receptors leading to more ++++ and more depol leading to more action potentials generated and thus seizure

Question 33

What are the four dopaminergic pathways in the brain?

Answer 33

Mesolimbic - memory and emotional behaviours
mesocorticol - cognition/motivation
nigrostriatal - controls movement
tuberoinfundibular - controls prolactin secretion

Question 34

What dopaminergic receptor is the main target for anti-psychotics?

Answer 34

D2 receptor

Question 35

What do 1st generation or typical drugs do?

Answer 35

block d2 receptors in all areas of the brain

Question 36

Anti-Psychotic Impacts on the pathways

Answer 36

Mesocorticol - dopamine blockade leads to more neg symptoms
Nigrostriatal - parkinsonian like side effects
Tuberoinfundibular - increased prolactin secretion
Mesolimbic - decrease positive symptoms associated with schizo (this is where we want it to work)