Basic Pharmacology Deck 1

Question 1

What drugs are ideal for sublingual administration?

Answer 1

lipid-soluble drugs that would be metabolized in the gut or liver (no first pass liver metabolism). Used for nitrates and certain hormones.

Question 2

What is the general order of bioavailability of oral drugs in the following forms (listed here alphabetically):
capsule
coated tablet
solution
suspension
tablet

Answer 2

solution > suspension > capsule > tablet > coated tablet

Question 3

What organs make up the ‘central compartment?’

Answer 3

heart, blood liver, brain and kidney. Drugs equilibrate rapidly.

Question 4

What organs make up the ‘peripheral compartment?’

Answer 4

adipose, skeletal muscle, other organs which are less well-perfused. Drugs equilibrate more slowly.

Question 5

What are xenobiotics?

Answer 5

Foreign compounds to which the body is exposed.

Question 6

In xenobiotic metabolism, what is the difference between Phase I and Phase II reactions?

Answer 6

Phase I: convert a drug to a more polar compound by introducing or unmasking polar functional groups, such as -OH, -NH2, -SH.
Phase II: Conjugation to newly established polar group with endogenous compounds such as: glucuronic acid, sulfuric acid, acetic acid or glycine.

Question 7

Name two inducers of P450 enzymes

Answer 7

phenobarbital; polycyclic aromatic hydrocarbons (such as those found in cigarette smoke or charcoal broiled foods).

Question 8

Name three inhibitors of P450 enzymes

Answer 8

erythromycin; ketonazole; cimetidine

Question 9

How can one prolong the duration of effect of penicillins?

Answer 9

Give probenecid, which competitively inhibits tubular secretion in the kidney.

Question 10

What substance increases percutaneous absorption of many drugs?

Answer 10

dimethyl sulfoxide (DMSO).

Question 11

What are the mechanisms by which ACh acts as either an excitatory or inhibitory transmitter in:

1) skeletal muscle
2) smooth muscle
3) cardiac muscle

Answer 11

1) skeletal - excitatory, increases Na+ and K+ conductance.
2) smooth - excitatory, increases Na+ conductance.
3) cardiac muscle - inhibitory, slows heart beat by increasing K+ conductance.

Question 12

Where is butyrocholinesterase found?

Answer 12

In blood and liver

Question 13

What action does the parasympathetic system have on the following organs?

1) eye
2) heart
3) GI
4) bladder
5) sweat, lacrimal glands.

Answer 13

1) constricts pupil (miosis)
2) decreases heart rate
3) increases motility and tone
4) contraction
5) increases secretion.

Question 14

What transmitter / receptor are found on parasympathetic postganglionic cells?

Answer 14

cholinergic muscarinic receptors.

Question 15

What is the catecholamine synthesis pathway?

Answer 15

Tyrosine -> dopa -> dopamine -> norepinephrine -> epinephrine

Question 16

What is the rate-limiting step in catecholamine synthesis?

Answer 16

Tyrosine -> DOPA (via tyrosine hydroxylase). enzyme is unique to catecholaminergic neurons and chromatin cells.

Question 17

What converts Dopamine to norepi, where does the conversion occur, and why does it matter?

Answer 17

Dopamine beta-hydroxylase; conversion occurs in storage vesicle, DBH is non-specific, will oxidize tyramine to octopamine.

Question 18

Where is most norepi located?

Answer 18

90-95% in storage vesicles; pumped in by VMAT-2 (vesicular monoamine transporter)

Question 19

What happens to norepi after being released into the synaptic terminal?

Answer 19

It is taken back up by norepi transporter (NET) - NET also transports DA and E.

Question 20

What substances inhibit NET?

Answer 20

cocaine; imipramine (tricyclic antidepressant).

Question 21

What metabolizes most NE and E released by the adrenal medulla?

Answer 21

catechol-O-methyltransferase (COMT) in the liver.

Question 22

What is the structure of adrenergic receptors and what are the effector molecules for:

1) alpha1 receptors
2) alpha2 receptors
3) beta receptors

Answer 22

All are GPCRs.

1) IP3/DAG pathway, calcium release.
2) Ginhibitory, causes PKA to go down.
3) Gstimulatory, causes PKA to go up.

Question 23

Where are alpha1 receptors found and what does their stimulation cause?

Answer 23

1) vascular smooth muscle -> contraction.

2) intestinal smooth muscle -> relaxation

Question 24

Where are alpha2 receptors found and what does their stimulation cause?

Answer 24

1) presynaptic nerve terminals -> decrease of NE release.

Question 25

Where are beta1 receptors found and what does their stimulation cause?

Answer 25

1) heart SA node and ventricles -> increased force and rate of contraction, AV nodal conduction velocity.

Question 26

Where are beta2 receptors found and what does their stimulation cause?

Answer 26

1) smooth muscle (vascular, bronchial, GI, genitourinary) - relaxation
2) liver - glycogenolysis, gluconeogensis

Question 27

What is rate-limiting step of acetylcholine synthesis?

Answer 27

concentration of choline in terminal.

Question 28

What does neostigmine do?

Answer 28

Inhibits AcChesterase

Question 29

What does pilocarpine do?

Answer 29

Stimulates muscarinic AcCh receptor, used to treat dry mouth, glaucoma.

Question 30

What does BoTx do?

Answer 30

Inhibits exocytosis of vesicles in cholinergic terminals.

Question 31

What protein metabolizes NE and Epi?

Answer 31

monoamine oxidase, found in mitochondrial membrane at terminal.