19.3 Pharm: Chemical transmission in the CNS

Question 1

What is the affinity of NA (extraneuronal and neuronal)

Answer 1

Extraneuronal: low affinity
Neuronal: high, 90-95% goes back into neuron

Question 2

What is the synthesis of a catecholaminen?

Answer 2

Tyrosine–>L-DOPA –> Dopamine –> NA –> A

Question 3

What happens to the NTM in Parkinsons?

Answer 3

Depletion of dopamine in basal ganglia

Question 4

Where in the brain does dependence due to dopamine actions occur?

Answer 4

Nucleus accumbens and ventral tegmental area

Question 5

What is the pituitary function of dopamine?

Answer 5

Prolactin secretion

Question 6

What in the brain does cocaine block?

Answer 6

NA, dopamine, serotonin uptake and blocks Na+ channels

Question 7

What deficiency occurs in Huntington’s Disease?

Answer 7

GABA deficiency

Question 8

Can a synapse be both excitatory and inhibitory?

Can the same NTM be both?

Answer 8

No, one or the other

Yes, NTM can (e.g. dopamine, serotonin-depends on R’ present)

Question 9

What are the types of ligand gated ion channels in the CNS (2)?

Answer 9

Excitatory- nicotinic (Na+ influx=depolarisation)

Inhibitory- GABA A (Cl- influx driven hyperpolarisation)

Question 10

What do GPCR do? What types of R’ are they?

Answer 10

Activate second messengers/modulate ion channel or enzyme

Muscarinic, a/b adrenoceptors