EFC Control I (lec 13)

Question 1

Na+ regulation driven primarily by Δs in what?

Primary effector is?

Answer 1

Blood volume, mainly BP Δs

RAAS

Question 2

H2O regulation driven primarily by Δs in what?

Primary effector is?

Answer 2

osmolarity and vol of ECF

ADH

Question 3

Aldosterone release stimulated by?

Answer 3

↑ [AngII] or plamsa [K+] stims adrenal cortex ->

stims aldosterone realease

Question 4

Aldosterone affects NaCl reabsorption how?

Answer 4

Stimulates Principle Cells in Late DCT and CD ->

Na+ reab, K+ secreted

Accounts for only 2% of Na+ filtration

Question 5

Angiotensin II fxns are? (3)

Answer 5

1) vasoconstriction
2) aldosterone release
3) Na+/H+ exchange in PCT

Question 6

Angiotensin II fxns all favor what? (2)

Answer 6

Na+ retention and ↑ arterial BP

Question 7

Ang II controlled by?

Answer 7

Renin

Question 8

Renin released by?

Answer 8

JGA

Question 9

Intrarenal baroreceptors (granular cells) affect Renin release how?

Answer 9

JGA responds to stretch in afferent arterioles

Renin release is INVERSELY proportional to aff art pressure

Question 10

Macula Densa affects Renin release how?

Answer 10

responds to flow DCT (GFR)

Renin release is INVERSELY proportional to GFR

Question 11

Renal SNS affects Renin release how?

Answer 11

stim of SNS near granular cells ->
stim β-receptors ->
release renin

Question 12

Atrial Natriuretic Peptide (ANP) release from?

In response to?

Answer 12

atria

response to high pressure

Question 13

ANP affects GFR how?

Answer 13

dilates aff arterioles, constricts eff arterioles ->

↑ GFR, ↑ NaCl filtered load

Question 14

ANP affects NaCl reab how?

Answer 14

Directly inhibits reab at CD by:

directly inhibiting renin/aldosterone secretion,
directly inhibiting Na+ reuptake by medulla CD

Question 15

ADH released from?

In response to?

Answer 15

pituitary

high plasma Osmo or
low plasma volume (hypovolemia)

Question 16

ADH affects H2O reab how? (3)

Answer 16

↑ aquaporins in CD basomemb,
↑ Na+/K+/2Cl-cotrans in LOH,
↑ CD permeability to urea

primary regulator of H2O balance

little effect on NaCl excretion

Question 17

ADH control: Baroreceptors?

Answer 17

respond to low plasma vol ->
↑ ADH ->
↑ H2O reab

Question 18

ADH control: Osmoreceptors?

Answer 18

respond to excess H2O ->
↓ ADH ->
↓ H2O reab

Question 19

Osmolar Clearance (Cosm) is?

Answer 19

rate of blood plasma cleared of osmotically active particles (ml/min)

Cosm = UosmV/Posm

Question 20

Normal Cosm = ?

Answer 20

1 to 2 ml/min

Question 21

Gaining osmoles (+ osmo balance) results in?

Progresses towards?

Answer 21

low Cosm

edema

Question 22

Low Cosm caused by?

Answer 22

↓ GFR, ↑ aldosterone, or dz that ↓ kidney ability to eliminate solute

Question 23

Dumping of osmoles results in?

Answer 23

loss of ECF ->

high Cosm

Question 24

High Cosm caused by?

Answer 24

diuretics, low aldosterone, or dz that ↓ kidney ability to reabsorb