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Flashcards in Renal Deck (26):
1

Effect of Aldosterone

increased Na+ reabsorption
increased H+ secretion

2

Total Body Water

42L

3

ICF Volume

28L

4

ECF Volume

14L (plasma + ISF)

5

ISF Volume

10.5L

6

Plasma volume

3.5 L

7

What percent of body mass is water?

50-70%

8

Order of most water filled to least water filled cells.

Plasma (94%) --> intersitium (77%) --> bone cells (20%) --> fat cells (10%)

9

What provides signals to stimulate or inhibit ADH release?

Stimulate --> Hypothalamic osmoreceptors
Inhibit --> Aortic arch and carotid baroreceptors

10

osmolaric threshold for thirst? For ADH release?

298; 280--- (max ADH secretion is 10pmol/L in this scenario)

11

Blood pressure threshold for ADH release?

10% below normal; max secretion for ADH is MUCH higher here (50 pmol/L)

12

What does SIADH cause?

very high water retention

13

The 2 functions of ADH and where they operate.

(1) Increased water permeability of the UPPER AND LOWER collecting duct

(2) Increased urea permeability of the LOWER collecting duct ONLY.

14

Osmolar Clearance Equation

Cosm= (Urinary Osm. x Urine flow) / Plasma osm.

15

ECV

Effective Circulating Volume

The portion of ECF volume within the vascular system that is effectively perfusing the tissues.

Should be the same as ECF but can vary in disease:
-CHF
-Hepatic Cirrhosis
-Pleural Effusion

These all DECREASE ECV.

16

The 3 factors which are important in stimulating renin secretion

-Perfusion pressure
-Sympathetic nerve activity
-Delivery of NaCl to the macula densa

17

Function of Angiotensin II

-stimulate ADH release
-stimulate thirst
-stimulate aldosterone release (which causes Na+ reabsorption and K+ secretion)

18

What stimulates movement of K+ into the cells, decreasing plasma K+?

Insulin, epinephrine, and aldosterone

19

Where does aldosterone function?

Distal tubules + collecting duct

20

Effect(s) of PTH, Calcitriol and Calcitonin on plasma [Ca2+]

PTH: increases plasma Ca2+
Calcitrol: increases plasma Ca2+
Calcitonin: decreases plasma Ca2+

21

Effect(s) of PTH, Calcitriol and Calcitonin on plasma [phosphate]

PTH: increases plasma phosphate reabsorption AND excretion
Calcitriol (vitamin D): increases plasma reabsorption and decreases excretion
Calcitonin: decreases plasma phosphate and increases excretion

22

Filtration Factor

GFR/RPF ratio

23

Diffusion-Trapped Ions

Mainly functions in distal tube and collecting duct.

NH3+ binds with H+ to form NH4+.

NH4+ is charged and is therefore lipid impermeable, thus trapping H+ from diffusing back into the cell. Body makes extra NH3+ during chronic acidosis

24

Principle Cells

Na+ channels, K+ channels, and Na+/K+ pumps

Mediated by Aldosterone (can increase or decrease number of pumps)

25

Normal PP...AHH values

pH = 7.35-7.45
PaCO2 = 35 mmHg- 45 mmHg
A- = 10 meq/L - 15 meq/L
H+= 35mM - 45 NM
HCO3- = 22mM- 28mM

26

Equation for RBF

RBF= effective RPF/ [1-hematocrit]

ERPF = clearance