Pharm 111 FINAL > Urinary > Flashcards

Urinary Flashcards

(58 cards)

Study These Flashcards
1
Q

What are some functions of the kidneys?

A
  • Filters 200L of blood plasma/day (put toxins/waste in urine)
  • Regulate total water volume and total solute conc
  • ensuring long-term acid-base balance
  • produces erythropoietin (regulate RBC production)
  • produces renin (regulate BP)
  • carrying out gluconeogenesis (as needed)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the 3 layers of supportive tissue that surround the kidney? from outer to inner

A
  1. Renal fascia: dense fibrous connective tissue
  2. Perirenal fat capsule: rapid weight loss affects this layer causing renal ptosis
  3. Fibrous capsule: transparent, protects kidneys from infection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the role of the minor calyces in the renal pelvis?

A
  • collect urine from renal pyramids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the urine flow?

A

Renal pyramid –> minor calyx –> major calyx –> renal pelvis –> ureter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the main difference between arterial flow and venous flow of kidneys

A

Venous flow has no segmental veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the arterial flow of kidneys (Ryan’s Stuck In Amy’s Car)

A

renal artery–> segmental –> interlobar –> arcuate –> cortical radiate

ALL to afferent arteriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the venous flow of kidneys (Can Amy Ignore Ryan?)

A

All from efferent arteriole

Cortical radiate –> arcuate –> interlobar –> renal veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the 2 parts of the renal corpuscle?

A
  1. Glomerular capsule
    - filtration slits in the visceral layer allow filtrate to pass into capsular space (have branching podocytes (foot processes))
  2. Glomerulus
    - Highly porous
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the 3 major parts of the renal tubule. What is their general function

A
  1. Proximal convoluted tubule (closest to renal corpuscle) PCT
    - reabsorption and secretion (large mitochondria)
  2. Nephron loop
    - descending & ascending limb
  3. Distal convoluted tubule DCT
    - More in secretion than reabsorption
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Differentiate between the 2 cell types of the collecting ducts

Microvili?
Function?

A
  1. Principle cells
    - short microvilli
    - maintain water & Na+ balance
  2. intercalated cells
    - abundant microvilli
    - type A & B help maintain acid-base balance of blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How is urine delivered through the collecting ducts?

A

collecting ducts recieve filtrate from MANY nephrons
- give pyramids their striped appearance
- ducts fuse together to deliver into minor calyces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Differentiate between cortical nephron and juxtamedullary nephron

  • Nephron loop length
  • What do their efferent and afferent arteriole supply?
A

Cortical (most of the nephrons)
- short nephron loop; further from cortex-medulla junction
- efferent arteriole supplies ONLY peritubular capillaries
- 2 capillary beds

Juxtamedullary
- long nephron loop; closer to cortex-medulla junction
- efferent arteriole supplies vasa recta AND peritubular capillaries
- 3 capillary beds
- important in production of concentrated urine

**Both of their afferent arterioles supplies the glomerulus capillaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why is there high blood pressure in the glomerulus? (2)

A
  • afferent arterioles are larger in diameter than efferent (which is what it uses)
  • glomerulus arterioles are high-resistance vessels
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the function of each capillary?
Glomerulus.. Pressure?
Peritubular.. pressure?
Vasa recta

A

Glomerulus
- filtration
- high pressure

Peritubular
- absorption of water and solutes
- Low pressure; porous cappilaries

Vasa recta
- parallel to nephron loops
- Formation of concentrated urine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the 3 cell populations of the Juxtaglomerular complex (JGC). Explain them
(MGE)

A
  1. Macula densa:
    - sense NaCl of ascending limb
  2. Granular cells:
    - sense blood pressure in afferent arterioles and secrete renin
  3. Extraglomerular mesangial cells:
    - connected with gap junctions, pass signals between macula densa + granular cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 3 processes involved in urine formation. Explain the process in simple terms.

A
  1. Glomerular filtration
    - produces cell and protein free filtrate
  2. Tubular reabsorption
    - selectively returns 99% of substances from filtrate to blood in renal tubules and collecting ducts
  3. Tubular secretion:
    - selectively moves substances from blood to filtrate in renal tubules and collecting ducts
    (getting rid of what you DON’T want)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

In Glomerular filtration, what do the fluids and solutes rely on to go through the filtration membrane?
Energy?
Reabsorption?
Passive?

A

Hydrostatic pressure

No
No
Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the role of the filtration membrane? Why does it occur?

A

Allows water/solutes to pass (smaller than 3 nm) (water, glucose, amino acids, nitrogenous wastes). It stops plasma proteins (or bigger molecules) from passing.

Keeps the plasma proteins in the blood to maintain COLLOID OSMOTIC PRESSURE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the 3 layers of the filtration membrane? Explain each one
FBF

A
  1. Fenestrated endothelium of the glomerular capillaries
    - make capillary beds more permeable to salt/water
    - block proteins from entering glomerular capsule
  2. Basement membrane
    - allows smallest proteins through
    - they use negatively charged glycoproteins to repel large proteins)
  3. Foot processes of podocytes
    - the foot process leave filtration slits
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the outward pressure in filtration called? What is the number? Why is it high?

A

Hydrostatic pressure in glomerular capillaries GC
- pushes water solutes out of blood

55mmHg
- efferent has a smaller diameter than afferent arterioles so it is a high-resistance vessel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the 2 inward pressures? What are their roles

A

Forces that inhibit filtrate formation
1. Hydrostatic pressure in capsular space CS
- filtrate pressure in capsule
- 15 mmHg

  1. Colloid osmotic pressure in capillaries
    - pull of proteins in blood
    - 30 mmHg
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the net filtration pressure? what is it directly proportional to and helps determine?

A

Forces out - forces in = 10 mmHg
- main factor for determining GFR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the GFR of our kidneys? what is GFR directly proportional to (3)?

A

GFR: volume of filtrate formed (120-125mL/min)

Proportional to
- NFP
- total SA available for filtration; # of nephrons
- Filtration membrane permeability (more permeable than other capillaries)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

When do intrinsic controls/ renal autoregulation occur?

Study These Flashcards
A
  • When MAP is 80-180 mmHg
  • autoregulation stops; extrinsic takes over
25
What are the 2 types of renal autoregulation (intrinsic control)
1. Myogenic mechanism 2. Tubuloglomerular feedback mechanism
26
Explain myogenic mechanism in intrinsic control
- inc BP = constriction of afferent arterioles - restrict blood flow into glomerulus - protect glomeruli from high BP (damaging) = decrease GFR **dec BP = dec stretch = dilation of afferent arterioles = inc GFR
27
Explain tubuloglomerular feedback mechanism of the intrinsic control. What occurs when GFR is increased?
Directed by macula densa cells (which respond to filtrate's NaCl) Increased GFR 1. dec reabsoprtion time=high NaCl levels in filtrate 2. constriction of afferent arteriole 3. Lower NFP and GFR = more time for NaCl reabsoprtion Decreased GFR= opposite
28
What is the purpose of extrinsic controls? When will it override intrinsic?
- Neural and hormonal (endocrine) mechanisms - regulate GFR to maintain systemic BP - override intrinsic when BV needs to be increased
29
How does the SNS play a role in extrinsic control? What occurs at normal conditions? What occurs in extremely low ECF (low BP)?
Normal conditions - blood vessels are dilated - renal autoregulation (intrinsic) win Low BP - norepinephrine and epinephrine are released causing: 1. vasoconstriction = inc BP 2. constriction of afferent arterioles = dec GFR overall: BV and BP increases
30
How does the hormones play a role in extrinsic control? What are the 3 pathways for renin release
Renin-angiotensin-aldosterone - main pathway for inc BP 3 pathways 1. Direct stimulation of granular cells by SNS 2. Macula densa cells stimulate granular cells when NaCl is low - release renin 3. Reduced stretch of granular cells
31
What are other factors affecting GFR?
Paracrine - adenosine - prostaglandin E2 Angiotensin II
32
What are the 2 routes of tubular reabsorption
1. Transcellular - through the apical membrane 2. Paracellular - through leaky tight junctions, specifically PCT - Moves Water, Ca2+, Mg2+, K+ and some Na+
33
How is Na+ transported on the basolateral membrane?
through the Na+/K+ ATPase pump (3 out, 2 in) (primary active transport) - K+ leaks out of the cell leaving a negative charge - Na+ outside cell with active transport creates the gradient for the entry in the apical side
34
How do Na+ and K+ return to the circulation?
via peritubular capillaries
35
How is Na+ reabsorbed on the apical membrane?
via secondary active transport - Na+ symport with glucose - export of Na+ at the basolateral membrane sets up the electrochemical gradient of Na+ - Na+ reabsorption is the main driving force for reabsorption of other nutrients
36
What are the 2 processes of tubular reabsorption of water through osmosis?
1. Obligatory water reabsorption - Aquaporins are always present in PCT (always happening) 2. Facultative water reabsorption - aquaporins are inserted in collecting ducts only if ADH is present - lipid soluble drugs + environment pollutants are reabsorbed this way - lipid sol: directly through cell - ions/urea: pass between cells
37
Define Transport Maximum (Tm)
Reflects number of carriers in renal tubules - when a substance reaches Tm, it is transported into urine for excretion
38
In the reabsorption by nephron loop, what is the descending loop and ascending limb permeable to
Descending limb: only permeable to water Ascending limp: permeable to solutes
39
What occurs in the thin and thick segments of nephron loop?
thin segment: - Passive diffusion of Na+ OUT Thick segment: - secondary active Na+/K+ - 2Cl- symporters - Na+/H+ antiporters to transport Na+ inco cells
40
When do the DCT and collecting ducts handle reabsorption? What is it regulated by?
PCT is not responsive to changing needs of the body - DCT is Regulated by: aldosterone, parathyroid hormone
41
When is atrial natriuretic peptide (ANP) released? what does it cause?
- in response to INC BV/BP - reduces blood Na+ Causes: - vasodilation - decreases water intake - dec BV BP
42
What occurs in tubular secretion
Selected substances are moved into filtrate (gets rid of stuff you don't want) - K+, H+, NH4+, creatinine, organic acids & bases, HCO3 Occurs almost completely in PCT
43
What is tubular secretion important for?
– Disposing of substances, such as drugs or metabolites – Eliminating undesirable substances that were passively reabsorbed (example: urea and uric acid) – Ridding body of excess K+ (aldosterone effect) – Controlling blood pH by altering amounts of H+ or HCO3– in urine
44
What is the osmolarity of our body fluid? What does 1 osmol refer to? MgCl2
300 mOsm 1 osmol = 1 mole of particle per L H2O MgCl2= 3 osmol
45
What are the 2 countercurrent mechanisms. Explain briefly
1. Countercurrent multiplier: - creates gradient in juxtamedullary nephrons 2. Countercurrent exchanger: - preserves gradient using blood flow in vasa recta
46
What are the 2 types of countercurrect mechanis?
1. Countercurrent multiplier - creates a gradient in the juxtamedullary nephrons 2. Countercurrent exchanger: - preserves gradient in the vasa recta
47
What occurs in the descending and ascending limb in the countercurrent multiplier?
Limbs are not in direct contact Descending limb: permeable to H2O - H2O passes out of filtrate --> 1200 mOsm Ascending limb: permeable to solutes - More NaCl pulled out --> pulls more water out of descending = saltier filtrate
48
What is the difference in mOsm between descending and ascending limbs of nephron loop? What is the mOsm of the final result of ruine?
200 mOsm 100 mOsm
49
How does the countercurrent exchanger work? (2)
- permeable to water and solutes - preserving the osmotic gradient from the countercurrent multiplier 1. preventing rapid removal of salt from interstitial space 2. Removing reabsorbed water
50
What is the net result of the countercurrent exchanger?
Net increase in BV and osmolarity
51
Explain dehydration and overhydration. mOsm? ADH? Aquaporins
Dehydration - ADH increases - 1200 mOsm - causes inc aquaporins (more water being reabsorbed) Overhydration - ADH decreases - 100 mOsm - aldosterone can play a role in this to reach 50 mOsm (increase Na+ reabsorption = promote water loss) - causes dec aquaporins (less water being absorbed)
52
How does urea help form medullary osmotic gradient. (3 steps)
1. Urea enters filtrate in the ascending thin + descending limb of nephron by facilitated diffusion 2. cortical collecting duct reabsorbs water, leaving urea behind 3. In deep medullary region, highly concentrated urea leaves collecting duct, enters interstitial fluid of medulla - urea moves back into ascending thin limb urea contributes to high osmolarity
53
What does a renal clearance of under 125ml/min and over mean? What can it help determine
125+ = substance was secreted (most drug metabolites) < 125 = substance is reabsorbed Help determine GFR
54
Where do infections tend to persist in the bladder? What is the capacity?
Trigone - 3 openings (2 for the ureters and one for the urethra) Max capacity 800-1000 mL
55
Why are females at a higher risk for UTI
Much shorter urethra than males
56
Differentiate between internal and external urethral sphincter
Internal - involuntary - contracts to open - smooth muscle External - voluntary - skeletal muscle Both are mostly pseudostratified
57
What are the 3 steps in micturition?
1. Contraction of detrusor by ANS 2. Opening (contraction) of internal urethral sphincter by ANS 3. Opening of external urethral sphincter (relaxation) by somatic voluntary system (VOLUNTARY)
58
Roles of PSNS and SNS in micturition
SNS - inhibits urine PSNS - promotes urine
Pharm 111 FINAL
flashcards
Decks in class (7)
# Cards
Brainscape helps you reach your goals faster, through stronger study habits.
© 2026 Bold Learning Solutions. Terms and Conditions