Adrenergic Drugs

Question 1

Synthesis of endogenous catecholamines

Answer 1

Tyrosine->DOPA->Dopamine (DA)->Norepinephrine (NE)->Epinephrine (E)

Question 2

MAO-A

Answer 2

Preferentially degrates 5HT, NE, DA

Question 3

MAO-B

Answer 3

Preferentially degrades DA

Question 4

Selegiline, isocarboxazid, phenelzine

Answer 4

MAOIs effective in treting depression

Question 5

a1 receptor

Answer 5

Location and Effects:
Vascular smooth muscle – contraction
UG smooth muscle – contraction
Intestinal smooth muscle – relaxation
Heart – Incr inotropy (contractility) and excitabiltiy
Liver – glycogenolysis and gluconeogenesis

Gq subtype signaling

Question 6

a2 receptor

Answer 6

Location and Effects:
Pancreatic B cells -- decr insulin secretion
Platelets -- aggregation
Nerve -- Decr NE release
Vascular smooth muscle -- contraction

Gi subtype signaling

Question 7

B1 receptors

Answer 7

Location and effects:
Heart – Incr chronotropy (HR), inotropy (contractility), incr AV node conduction velocity
Renal juxtaglomerular cells – incr renin secretion

Gs signaling

Question 8

B2 receptors

Answer 8

Location and Effects:
Smooth muscle – relaxation
Liver – glycogenolysis and gluconeogenesis
Skeletal muscle – glycogenolysis and K uptake

Gs signaling

Question 9

B3 receptors

Answer 9

Adipose tissue – lipolysis

Gs signaling

Question 10

D1 receptors

Answer 10

Gs signaling

Expressed in kidneys, mesentery, coronary arteries

Causes relaxation in vascular smooth muscle

Question 11

D2,D3, D4

Answer 11

Gi signaling

Question 12

D5

Answer 12

Gs signaling

Question 13

Nigrostriatal pahtway

Answer 13

Projects from substantia nigra to corpus striatum

D1 and D2 receptors

Degeneration results in Parkinson’s

Question 14

Mesolimbic Pathway

Answer 14

From ventral tegmental area to cerebral cortex and nucleus accumbens

Invoved w/ schizophrenia and addiction

Question 15

Tubero-infundibular pathway

Answer 15

From hypothalamus (arcuate and para-ventricular nuclei) to the anterior pituitary

Inhibits release of prolactin

Question 16

Area postrema

Answer 16

Associated w/ emesis (vomiting)

Question 17

Noradrenergic system

Answer 17

From locus coeruleus to cerebral cortex, hypothalamus, cerebellum

Tx of ADHD

Pathway of action of cocaine and amphetamine

Question 18

Nucleus tractus solitarius

Answer 18

REceives input from baroreceptors and chemoreceptors and regulates blood pressure

Question 19

Epinephrine

Answer 19

Hormone w/ higher affinity for B-receptors

Incr HR and contractility, decr peripheral vascular resistance, incr blood flow to muscles, dilates airways

Question 20

Norepinephrine

Answer 20

Higher affinity for a-receptors

Incr peripheral vascular resistance, decr capacitance of vessels, incr HR and contractility

Question 21

Dopamine

Answer 21

Vasodilation in renal, mesenteric, coronary, and cerebral vasculature

Bind to all types of adrenergic receptors

Mediates Parkinson’s and schizophrenia

Question 22

Isoproterenol

Answer 22

B-receptor selective

Vasodilation, incr HR and contractility

Ind. for bradycardia and heart block

Question 23

Midodrine

Answer 23

Metabolite is selective a1-agonist

Tx of orthostatic hypotension by vasoconstriction to incr blood pressure

Question 24

Phenylephrine

Answer 24

a1-selective agonist

Long half life

Nasal decongestion, mydriasis (dilated pupils), incr BP, antidote for chronic erection

Question 25

Methyldopa, clonidine, and tizanidine

Answer 25

Selective a2-receptor agonists in the brain

Treat hypertension (doesn’t seem logical but apparently this is the case)

Question 26

Dobutamine

Answer 26

B1-receptor agonist

More prominent incr in contractility than HR

Ind. in severe heart failure

Question 27

Metaproterenol, terbutaline, albuterol, ritodrine, formoterol, salmeterol

Answer 27

-erol for most of them

B2-receptor agonists

Ind. for asthma and COPD

May cause hypoxia, arrhythmias