Adrenergic neuron blockers and ganglionic blockers

Question 1

Adrenergic neuron blockade MOA: Guanethedine

Answer 1

Inhibit NE release from adrenergic nerve terminals
Deplete catecholamine stores
Forms false neurotransmitters

Question 2

Adrenergic neuron blockade MOA: Bretylium

Answer 2

Inhibit NE release from adrenergic nerve terminals

Question 3

Adrenergic neuron blockade MOA: Reserpine

Answer 3

Deplete catecholamine stores

Question 4

Adrenergic neuron blockade MOA: Methyldopa

Answer 4

Deplete catecholamine stores

Forms false neurotransmitters

Question 5

Adrenergic neuron blockade MOA: Pargyline

Answer 5

MAO inhibitor

Question 6

Adrenergic neuron blockade MOA: Metyltyrosine

Answer 6

Interfere with catecholamine synthesis

Question 7

Adrenergic neuron blockade MOA: 6-Hydroxydopamine

Answer 7

Destroy adrenergic nerve fibers

Question 8

Adrenergic neuron blocker which is worst for orthostatic hypotension ADR

Answer 8

Guanethedine and congeners

Question 9

Reserpine: solubility, MOA, ADR, effect on CVS/Brain/GIT

Answer 9

Readily enters the brain
MOA: Irreversibly binds tightly to adrenergic storage vesicles: depletion of catecholamines in CNS and adrenal medulla
ADR: Extrapyramidal symptoms, Depression
CVS: decreased HR, CO, PVR, BP
-Salt and water retention–> pseudotolerance, edema
Brain: sedation, EPS, depression
GIT: parasympathetic predominance

Question 10

Methyldopa: indication, MOA, ADR

Answer 10

Indication: Hypertension during pregnancy
MOA: central a2 agonist: decrease PVR; false neurotransmitter
ADR: Sedation at onset, EPS, amenorrhea, postural hypotension, lactation

Question 11

Guanethedine: Indication, solubility, MOA

Answer 11

Indication: severe form of hypertension
Polar, cannot cross BBB, no sedation
Bretylium-like: blocks NE release by blocking impulse conduction in nerve terminals
Cocaine-like: inhibits neuronal uptake
Reserpine-like: catecholamine depletion
Tyramine-like: rapid release of NE from stores (sympathomimetic)

Question 12

Guanethedine: ADR

Answer 12

Profound sympathoplegia

Pharmacologic sympathectomy

Question 13

Metyrosine: MOA

Answer 13

Inhibits tyrosine hydroxylase

Question 14

6-Hydroxydopamine: MOA

Answer 14

selectively neurotoxic for noradrenergic terminals
Converted to quinone–> chemical sympathectomy
Destruction of nerve fibers

Question 15

Treatment of lifethreatening ventricular arrhytmias that dont respond to lidocaine or procainamide

Answer 15

Bretylium

Question 16

currently licensed as an orphan drug for Tourette’s syndrome

Answer 16

Mecamylamine

Question 17

MOA of Trimetaphan

Answer 17

Competitive ganglionic blocker