Intro to Antihypertensive Agents I

Question 1

prehypertension

Answer 1

SBP 120-139
DBP 80-89

recommend lifestyle changes

Question 2

stage 1 HTN

Answer 2

SBP 140-159
DBP 90-99

begin treating HTN

Question 3

stage 2 HTN

Answer 3

SBP >160

DBP >100

Question 4

mean arterial pressure

Answer 4

MAP = CO x TPR

Question 5

cardiac output

Answer 5

CO = HR x SV

Question 6

drug strategy with HTN

Answer 6

reduce CO

reduce TPR

Question 7

compensation for HTN meds**

Answer 7

reflex tachycardia - increased symapthetics

edema - increased renin activity

**so can add different drug to counteract

Question 8

weight reduction

Answer 8

5-20 decreased SBP

Question 9

DASH diet

Answer 9

8-14 decreased SBP

Question 10

dietary sodium reduction

Answer 10

2-8 decreased SBP

Question 11

physical activity

Answer 11

4-9 decreased SBP

Question 12

moderation of alcohol

Answer 12

2-4 decreased SBP

Question 13

antihypertensive sites of action

Answer 13

arterioles
venules
heart
kidneys

Question 14

major classes of antihypertensive meds

Answer 14

• diuretics
• agents blocking ANG action
• direct vasodilators
• sympathoplegic agents

Question 15

diuretics

Answer 15

act at kidney tubules

Question 16

agents that block ANG action

Answer 16

• angiotensin receptors of vessels
• beta-receptors of JG cells
• ACE inhibitors
• renin inhibitors

Question 17

direct vasodilators

Answer 17

on vascular smooth m.

Question 18

sympatholytics

Answer 18

• vasomotor center of brain
• beta-receptors of heart
• alpha receptor of vessels
• beta receptors of JG cells

Question 19

patients with CKD

Answer 19

ACE inhibitors

ARB (angiotensin receptor blocker)

Question 20

black patients without CKD

Answer 20

thiazide diuretic

calcium channel blockers

Question 21

nonblack patient without CKD

Answer 21

thiazide diuretic**
ACE inhibitor
ARB
CCB

Question 22

kidney blood flow

Answer 22

20-25% of CO

Question 23

carbonic anhydrase

Answer 23

formation/dehydration of carbonic acid in proximal tubule

Question 24

proximal tubule activity

Answer 24

• active reabsorption of HCO3, NaCl, K, glucose, AAs
• passive reabsorption of water
• Na/K pump maintains Na concentration in cell low
• carbonic anhydrase

**site of action of carbonic anhydrase inhibitors

Question 25

thin descending loop of henle

Answer 25

water reabsorption

Question 26

thin ascending loop of henle

Answer 26

impermeable to water, other ions/solutes

Question 27

thick ascending loop of henle

Answer 27

Na/H/2Cl cotransport | -established concentration gradient

Question 28

K leak in thick ascending limb

Answer 28

high K in cells - K diffuses back to lumen -creates positive charge- drives the paracellular reabsorption of Mg, Ca

Question 29

tubular fluid

Answer 29

concentrated in descending limb and diluted in ascending limb

Question 30

distal convoluted tubule

Answer 30

- 10% NaCl reabsorbed - impermeable to water Na/Cl cotransporter - active NaCl out of lumen -Ca is reabsorbed by calcium channels

Question 31

thiazide diuretics

Answer 31

blocks Na/Cl cotransporter in the distal convoluted tubule

Question 32

Ca reabsorption

Answer 32

distal convoluted tubules - has Ca channels - regulated by PTH -increased PTH/increased reabsorption

Question 33

most important site of K secretion**

Answer 33

collecting tubule -site where all diuretic induced K balance changes occur **most diuretics - hypokalemia - bc more sodium to CT lumen > more Na pulled out at ENaC > causes more K secretion** **also hypokalemia with metabolic alkalosis > lumen negative favors retention of H+ in lumen > urine pH goes down > body pH goes up** more Na to CT - more K secretion

Question 34

collecting tubule

Answer 34

- proton pump - increased urine acidity - ENaC - 2-5% Na reabsorption creates electrical gradient that facilitates K secretion down concentration gradient

Question 35

aldosterone

Answer 35

increased ENaC and basolateral Na/K ATPase in collecting tubule water retention - increase in blood volume and BP

Question 36

ENaC

Answer 36

in collecting tubule - increased Na reabsorption - 2-5% of total - does create gradient to facilitate K secretion

Question 37

ADH

Answer 37

aka vasopression - released from pituitary - increases aquaporin 2 on collecting tubules - via V2 receptor -increased water reabsorption

Question 38

ADH level control

Answer 38

serum osmolality and volume status

Question 39

diuretics

Answer 39

- carbonic anhydrase inhibitors - loop diuretics - thiazide diuretics - potassium-sparing diuretics

Question 40

diuretic use

Answer 40

increase rate of urine flow edematous and nonedematous states

Question 41

site of loop diuretics

Answer 41

Na/K/2Cl cotransporter in thick ascending limb

Question 42

site of thiazide diuretics

Answer 42

Na/Cl cotransporter

Question 43

site of potassium sparing diuretics

Answer 43

sodium channels

Question 44

site of potassium sparing diuretics

Answer 44

mineralocorticoid receptors and sodium channels