Renal 5

Question 1

Regulation of Tubular
Reabsorption
Essential to maintain a precise balance between

Answer 1

GFR and tubular reabsorption.

Question 2

Tubular reabsorption controlled by (3)

Answer 2

Local Control
Mechanisms, Nervous System, and Endocrine
System

Question 3

Reabsorption of some solutes can be individually

—.

Answer 3

adjusted

Question 4

Local Control Mechanisms (3)

Answer 4

Tubuloglomerular Feedback Response (TGF)
Glomerulotubular Balance (GTB)
Arterial Pressure (pressure natriuresis/diuresis)

Question 5

Systemic Control Mechanisms (2)

Answer 5

Hormones

Sympathetic Nervous System

Question 6

Hormones (5)

Answer 6

• aldosterone
• angiotensin II
• antidiuretic hormone (ADH)
• atrial natriuetic peptide (ANP or ANF)
  ₋ parathyroid hormone

Question 7

TGF Response: Autoregulation of GFR. (3)

Answer 7

Keeps GFR constant
Afferent and Efferent arteriolar resistance related to flow rate of NaCl by macula
densa
Example: GFR increase-increased NaCl to macula densa- TGF response decreases
GFR

Question 8

Glomerular Tubule Balance (GTB): Autoregulation

of PT reabsorption rate (4)

Answer 8

PT reabsorption rate related to tubular load
As tubular LOAD increases, rate of
REABSORPTION increases.
Depends on changes in peritubular capillary and
renal interstitial fluid Starling’s forces.
Example: GFR increase-GT balance increases PT
Na+/H20 reabsorption to maintain Na+/H20
balance

Question 9

Together these two mechanisms help to

Answer 9

prevent overloading of the distal tubule

segment when GFR increases due to pressure changes or other disturbances

Question 10

Assures — may be maintained

Answer 10

Homeostasis

Question 11

Small increases in MAP can cause marked increases in urinary (2)

Answer 11

Na+ and H2O excretion.

 Mechanisms not understood

Question 12

Normal kidney function and pressure natriuresis mechanisms assure that

Answer 12

large changes in salt and water intake accommodated with only minor changes in ECF volume, CO, and MAP

Question 13

Aldosterone: Cellular Mechanism

Stimulates

Answer 13

Na+ reabsorption and

K+ Secretion

Question 14

Aldosterone: Cellular Mechanism

onest and duration

Answer 14

slow onset

long duration

Question 15

Aldosterone: Cellular Mechanism

increases (2)

Answer 15

number and activity

activity

Question 16

Control of Aldosterone Secretion

increase (2)

Answer 16

 Increased plasma K+

 Angiotensin II

Question 17

Increase
 Increased plasma K+
 Angiotensin II
(changes associated with

Answer 17

Na+
and volume depletion or low
blood pressure)

Question 18

Control of Aldosterone Secretion

Decrease (2)

Answer 18

 Atrial natriuretic peptide
(ANP/ANF)
 Increased Na+ concentration
(osmolarity; weak)

Question 19

Decrease
 Atrial natriuretic peptide 
(ANP/ANF)
 Increased Na+ concentration 
(osmolarity; weak)
(changes associated with

Answer 19

increased Na+ and volume or

high blood pressure)

Question 20

Other Effects of Aldosterone (3)

Answer 20

Increases H+ secretion by intercalated cells of late distal & cortical
collecting tubule membrane: excess aldosterone levels may cause
metabolic alkalosis.
Increases Na+ reabsorption and K+ secretion by sweat and salivary
glands.
Increases Na+ absorption by intestinal (colon) mucosa.

Question 21

Angiotensin II:
Cellular Mechanism
major regulator of (2)

Answer 21

na and water reabsorption

Question 22

Angiotensin II:
Cellular Mechanism
occurs in most

Answer 22

nephron segments

Question 23

Angiotensin II:
Cellular Mechanism
stimulus (2)

Answer 23

decreased MAP

decreased ECFvol

Question 24

Angiotensin II: 
Cellular Mechanism
effector responses (6)

Answer 24

 Stimulates aldosterone production.
 Directly increases Na+ reabsorption (proximal, loop, distal,
collecting tubules).
 Increases H+ secretion
 Constricts efferent arterioles and increases GFR
 Constricts systemic arterioles, increasing TPR and MAP
 Increases Aldosterone secretion from Zona Glomerulosa

Question 25

ADH: Cellular Mechanisms increases

Answer 25

water reabsorption

Question 26

ADH: Cellular Mechanisms location

Answer 26

late DT and CD

Question 27

ADH: Cellular Mechanisms Stimulus (2)

Answer 27

increased ECFosm | decreased MAP

Question 28

ADH: Mechanisms of Action (3)

Answer 28

```  Increases H2O permeability via activation of Gαs Protein linked receptor  Activates cAMP  Increases the synthesis and insertion of AQP-2 into luminal membrane. ```

Question 29

Atrial Natriuretic Peptide (ANP) increase decrease

Answer 29

increase GFR | decrease na reabsorption (increase na excretion)

Question 30

ANP | Stimulus

Answer 30

 Secreted by cardiac atria in response to stretch (increased blood volume).

Question 31

ANP: Effector Responses (4)

Answer 31

``` Effector Responses  Directly inhibits Na+ and H2O reabsorption in PT  Increases GFR (dilates afferent, constricts efferent arterioles).  Inhibits renin release and aldosterone formation.  Helps to minimize blood volume expansion (CHF). ```

Question 32

hormone: site of action: effect:

Question 33

hormone: site of action: effect:

Question 34

hormone: site of action: effect:

Question 35

hormone: site of action: effect:

Question 36

SNS Decreases (2) Excretion

Answer 36

Na+ and H2O

Question 37

SNS Decreases Na+ and H2O Excretion: (4)

Answer 37

```  Constricts arterioles.  Stimulates renin release.  Decreases GFR and renal blood flow.  Directly stimulates Na+ reabsorption via α receptors on tubule epithelial cells in PT and TAL. ```

Question 38

Total Ca++ amount in body

Answer 38

1100 g,  99% stored in bones

Question 39

Total Body Ca++ (3)

Answer 39

- 0.1% ECF - 1% ICF/IC compartment - Majority in bone

Question 40

ECF --- tightly regulated

Answer 40

Ca++

Question 41

Ca | Critical for: (6)

Answer 41

``` ⁻ Normal cell function ⁻ Neural transmission ⁻ Membrane excitability ⁻ Bone structure ⁻ Blood Coagulation ⁻ Intracellular signaling ```

Question 42

--- Ca++ is form most | important for functions in body

Answer 42

ionized

Question 43

--% of Plasma | Ca++ Filtered

Answer 43

60

Question 44

--% of Filtered Ca++ | Reabsorbed in PCT

Answer 44

65

Question 45

---% Reabsorbed in Loop of Henle

Answer 45

25-30

Question 46

---% Reabsorbed in Distal and Collecting Tubule

Answer 46

4-9

Question 47

--% Excreted

Answer 47

1

Question 48

PTH Regulates Ca++ Reabsorption in (2)

Answer 48

TAL and DT

Question 49

Luminal | Absorption (3)

Answer 49

``` 50% by para- cellular bulk flow; passive Favored by +8 mV luminal charge 50% transcellular; entry passive ```