Antihypertensives

Question 1

T/F
Systemic vascular resistance is increased by:
β2-receptor activation

Answer 1

False. β2-receptor activation causes peripheral vasodilatation.

Question 2

T/F
Systemic vascular resistance is increased by:
Vasopressin

Answer 2

True. Vasopressin acts on the V1-receptor in smooth muscle to cause vasoconstriction.

Question 3

T/F
Systemic vascular resistance is increased by:
Atrial natriuretic peptide

Answer 3

False. Atrial natriuretic peptide stimulates guanylyl cyclase and increases smooth muscle relaxation

Question 4

T/F
Systemic vascular resistance is increased by:
α1-receptor activation

Answer 4

True. α1-receptor activation causes peripheral vasoconstriction.

Question 5

T/F
Systemic vascular resistance is increased by:
Angiotensin II

Answer 5

True. Angiotensin II acts on AT1-receptors causing arteriolar vasoconstriction.

Question 6

T/F

Clonidine Is an α1-receptor antagonist

Answer 6

False. Clonidine is an α2 agonist and has some α1 agonist action

Question 7

T/F

Clonidine Causes a reduction in gastric motility

Answer 7

True. Side effects include dry mouth, sedation, depression, reduced gastric motility and reduced cerebral perfusion.

Question 8

T/F

Clonidine Causes sedation

Answer 8

True. It can be given via the epidural route at approximately 30 μg/h. It can also be given orally.

Question 9

T/F

Clonidine Cannot be given via the epidural route

Answer 9

False

Question 10

T/F

Clonidine Decreases cerebral blood flow

Answer 10

True

Question 11

T/F Sodium Nitroprusside Can be given orally

Answer 11

False. Can only be given intravenously once it has been reconstituted from a powder preparation.

Question 12

T/F Sodium Nitroprusside Attenuates hypoxic pulmonary vasoconstriction

Answer 12

True. It can increase shunt by impairing hypoxic pulmonary vasoconstriction.

Question 13

T/F Sodium Nitroprusside Breaks down into five cyanide ions for every SNP molecule

Answer 13

True. Broken down non-enzymatically within red blood cells to produce five cyanide ions per molecule.

Question 14

T/F Sodium Nitroprusside Acts solely on arterioles

Answer 14

False. It acts mainly on arterioles but can affect venules.

Question 15

T/F Sodium Nitroprusside Shifts the cerebral autoregulation curve to the right

Answer 15

False. Cerebral autoregulation is maintained during SNP infusion.

Question 16

T/F Nifedipine is in the same class as Diltiazem

Answer 16

False. Nifedipine works in a similar way to Amlodipine.

Question 17

T/F Nifedipine causes reflex tachycardia

Answer 17

True. Peripheral arteriolar vasodilatation can cause a rebound tachycardia

Question 18

T/F Nifedipine can reduce the MAC of a volatile agent

Answer 18

True

Question 19

T/F Nifedipine inhibits thromboxane production

Answer 19

True

Question 20

T/F Nifedipine causes bronchodilation

Answer 20

False. Has no effect on bronchioles

Question 21

T/F Hydralazine is metabolised by acetylation

Answer 21

True. Hydralazine is metabolized to acetylated and hydroxylated metabolites.

Question 22

T/F Hydralazine Is thought to work via β2-receptor stimulation

Answer 22

False. It is thought to work by increasing intracellular cGMP.

Question 23

T/F Hydralazine can cause lupus like symptoms

Answer 23

True. Lupus type syndrome can be seen particularly after long term use in women.

Question 24

T/F Hydralazine is contraindicated in pregnancy

Answer 24

False. It is given intravenously in severe pregnancy induced hypertension.

Question 25

T/F Hydralazine can be given orally

Answer 25

True. It can be given orally but bioavailability is variable, from 25-55%.