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Flashcards in Glomerular Filtration Deck (29)
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1
Q

What is the function of Granular Cells? Cells of the Macula Densa?

A

Granular cells —> Renin Release

Macular Densa —> Sensing flow of filtrate

2
Q

What do the sympathetic nerves in the glomerulus project to?

A

Smooth muscle cells and granular cells of afferent arterioles

3
Q

What are the three layers of glomerular capillaries?

A
  1. Fenestrated Endothelium
  2. Negatively charged Basement membrane
  3. Podocytes
4
Q

What are the factors which determine filter ability?

A
  1. Molecular weight

2. Molecular charge (Negative charge)

5
Q

What impedes the filtration of albumins?

A

Negative charge of basement membrane of glomerulus

6
Q

What is the exception for proteins in the urine?

A

Tam-Horsfall protein - function unclear maybe kidney stone prevention

7
Q

What is Profound proteinura, and what is it’s major effect on the body?

A

3 g/day

Can lead to low plasma protein concentration and a decrease in plasma osmotic pressure —> Edema

8
Q

Describe Nephrotic Syndrome

A
  • Periorbital Edema
  • Decrease in plasma albumin
  • Overall increase in swelling/edema
9
Q

What is glomerulonephritis?

A

Autoimmune

Antigen-Antibody complex attack wall of capillaries and cause inflammation

Hematura, Other blood cells in urine and glomerulus; Mesangial cell contraction and proliferation

Can lead to Renal insufficiency, Oliguria, or Anuria

10
Q

Describe minimal change disease

A

Proteinurea

  • Podocytes damaged and/or negative basement membrane diminished
  • Typically affect children
  • Diffuse loss of podocytes foot processes; No capillary damage detected from microscope

***Treat with Steroids

11
Q

How does Chronic kidney disease develop?

A

Antigens —> Inflammation —> Mesangial proliferation —> Decreased GFR

12
Q

How does Diabetic nephropathy differ in appearance to other?

A

Begins with an increase in GFR and decreases after Mesangial proliferation?

13
Q

What is GFR and what is the normal value?

A

Volume of filtrate per unit time in nephron from plasma.

100 ml/min

14
Q

What are the forces which underlie filtration? How is Net Filtration Pressure calculated?

A

(Beginning Of arterioles)
Out of Cappilary:

Hydrostatic pressure (PH) - 45 mmHg

Into capillary:

Hydrostatic Pressure (PBS) - 10 mmHg

Osmotic pressure (PO) - 25

NFR = PH - PBS - PO

15
Q

How is GFR calculated?

A

GFR = NFP X Kf

Kf = Filtration coefficient which is 100X greater then in systemic capillaries

16
Q

How does NFP change as you continue along the Glomerular capillary?

A

NFP Decreases

As fluid moves out, Osmotic pressure increases

17
Q

How dose Hydrostatic pressure change GFR?

A

Afferent Vasoconstriction:

  • INC Resistance
  • Decrease in RBF
  • DEC Hydrostatic pressure in Capillary —> DEC GFR

Efferent Vasoconstriction:

  • INC Hydrostatic Pressure
  • INC GFR
18
Q

How does ANP affect GFR?

A
  • DEC Afferent resistance
  • INC Efferent resistance
  • INC NFP —> INC GFR*
19
Q

What is responsible for increased GFR in initial stages of diabetes?

A

Increased glomerular hypertension

20
Q

What is the treatment for Diabetic nephropathy and how does it work?

A

Cilazapril —> Dilation Of efferent arterioles —> Reduced glomerular hypertension —> Reduced GFR and Proteinura

21
Q

How does Contritcion of Ureters Decrease GFR?

A
  • INC in PBS (opposing force in NFP)

- Net decrease in GFR

22
Q

How does the kidney autoregulate during intense physical exercise?

A
  • Afferent arteriole Contraction plays major role

- Changes in vascular resistance results in constant RBF and GFR

23
Q

How is RPF calculated?

A

RPF = RBF X (1-Ht)

24
Q

How is GFR related to RPF?

A

GFR = Filtration fraction (FF) X RPF

25
Q

How does high creatinine levels tell us?

A

High creatinine —> Little plasma filtration —> Renal insufficiency

26
Q

What is Filtered load and how calculated?

A

Mass of substance filtered per minute

GFR X Pz

Pz = Plasma concentration

27
Q

How is Renal clearance calculated?

A

Clz = (UF x Uz)/Pz

28
Q

What is the cause of presently azotemia?

A

Renal hypofusion —> INC BUN

29
Q

How do postrenal and prerenal Azotemia differ?

A

In postrenal azotemia, reabsorption of Na+ is not increased