Renal- Rbf & Gfr

Front 1

list the 3 components of the Juxtaglomerular apparatus

Back 1

1.Renin-producing Granular cells.

2.Macula Densa.

3.Extraglomerular matrix (mesangial cells).

Front 2

Where is MOST of the Na and H2O reabsrobed in the nephron?

Back 2

Proximal Tubule

Front 3

Which part of the loop of henley is HIGHLY permeable to Water? NaCl?

Back 3

1.Water: Thin descending limb (creates hyperosmolar urine).

2.NaCl: Thin Ascending limb & Actively in the THICK Ascending limb (create Hypoosmolar urine).

Front 4

What kind of urine presents to the Distal Convoluted tubule?

Back 4

DILUTE!!

Front 5

What is the target of Loop Diuretics? Where is it located?

Back 5

The Tri-Transporter (Na/2Cl/K) in the Thick Ascending limb of the loop of Henley.

Front 6

What affect to does ADH have on the reabsorption of Water?

Back 6

It INCREASES the number of aquaporin channels in the collecting ducts whihc will INCREASE reabsorption of H2O

Front 7

What structure is the juxtaglomerular apparatus in close proximity to?

Back 7

Renal Corpuscle

Front 8

What cells serve as INTRA-renal baroreceptors

Back 8

Renin-producing granular cells.

**They also produce and store the Renin

Front 9

What does the Macula Densa monitor? what 3 things does it influence? ***TEST

Back 9

MD detects NaCl concentrations.

**Influences:
1.RBF.
2.GFR.
3.Release of Renin.

Front 10

What does GFR actually measure/represent? ***TEST

Back 10

The VOLUME of filtrate formed per unit TIME.

***Vol/Time (180L/day)

Front 11

Equation for GFR

Back 11

GFR = Kf x NFP.

**Kf: filtration coefficient, NFP: net filtration pressure

Front 12

Equation for NFP

Back 12

NFP = (PGC + πBC) – (PBC + πGC).

**πBC is negligable, so it is NFP = (PGC - PBC - πGC)

Front 13

What does πGC stand for?

Back 13

Glomerular capillary oncotic pressure

Front 14

List the 4 main direct determinants of GFR ***

Back 14

1.Kf.

2.PGC.

3.PBC.

4.πGC

Front 15

What happens if Kf Inc? Dec?

Back 15

1.Inc Kf: Inc GFR due to Inc glomerular SA (relaxation of mesangial cells).

2.Dec Kf: Dec GFR due to Dec glomerular SA

Front 16

What happens if PGC INC? Dec?

Back 16

1.Inc PGC: Inc GFR due to Inc renal artery pressure AND efferent VC with afferent VD.

2.Dec PGC: Dec GFR

Front 17

What happens if PBC Inc? Dec

Back 17

1.Inc PBC: Dec GFR due to INC intratubular pressure from an obstruction of a downstream tubule.

2.Dec PBC: Inc GFR

Front 18

What happens if πGC INC? Dec?

Back 18

1.Inc πGC: Dec GFR b/c there are stronger forces pulling water back into the GC from BC.

2.Dec πGC: Inc GFR

Front 19

Effect on GFR with afferent VC

Back 19

Dec GFR via Dec PGC & RBF

Front 20

Effect on GFR with efferent VC

Back 20

Inc GFR via Inc PGC

Front 21

Effect on GFR with BOTH afferent and efferent VC due to a large sympathetic outflow

Back 21

MAINTAINS GFR despite the DEC in RBF

Front 22

Is the filtration equilibrium reached faster with slow of fast glomerular plasma flow?

Back 22

SLOW (low) **You will filter our MORE fluid and πGC will increase much faster

Front 23

Does Low of High glomerular plasma flow have more wasted capillary space?

Back 23

Low.

**reaches equilibriuim faster!!

Front 24

____ Glomerular Plasma Flow has greater NFP and more glomerulus available for filtration at ANY one point

Back 24

High

Front 25

Does RBF or plasma flow have an independent affect on GFR outside of vessel VC and VD?

Back 25

Yes, were you even paying attention to the last 2 note cards? Is anyone even listening to me?

Front 26

What is the equation for Filtration fraction (FF)? is it greater at higher or lower plasma flows?

Back 26

FF = GFR/RBF (vol of filtrate from a given volume of plasma entering the glomeruli).

**It is Greater at LOWER renal plasma flows

Front 27

Why exactly does GFR decrease with afferent VC?

Back 27

b/c both PGC and RBF fall

Front 28

Describe the effects of PGC and RPF on GFR when the efferent arteriole is VC

Back 28

At lower efferent arteriolar VC, GFR will INCREASE due to Inc PGC. However, at higher efferent VC, GFR will DECREASE due to falling RBF

Front 29

What is Angiotensin II (AngII) affect on GFR

Back 29

It maintains VC of efferent arterioles more so than on afferent arterioles, this will INCREASE GFR

Front 30

Therefore if AngII is blocked, by and ACEI or ARB, what happens to GFR?

Back 30

It will not be maintained at lower artery pressure like it normally would. It will Dec much sooner with a fall in pressure

Front 31

You give a person a drug that dilates the afferent arteriole and constricts the efferent arteriole by the same amounts. What effect will this have on GFR, RBF, and FF?

Back 31

1.GFR: Inc due to Inc PGC.

2.RBF: NO change.

3.FF: Inc.

**You will also start to inc GC oncotic pressure.

Front 32

Your patient has entered the ER after a motorcycle accident. His blood pressure is very low and he is tachycardic. You believe he has lost a great deal of blood volume. In the reflex response to his hypotension, what is happening with RAAS and FF?

Back 32

RAAS: INCREASES.

FF:INCREASES due to Inc AngII

Front 33

In relation to the last notecard, Describe the peritubular capillary hydrostatic and oncotic pressures that result from the change in FF and the movement of fluid and solutes.

Back 33

Kidney is trying to Inc recovery of Na and H2O

Front 34

Your patient has renal artery stenosis. What effect will the stenosis have on RAAS and subsequently on GFR?

Back 34

Activates RAAS b/c it is seen as hypoperfusion(dec in renal BF)

Front 35

With efferent VC, what dominates control over GFR at less severe VC? More severe VC?

Back 35

Less severe VC: PGC.

More severe VC: RBF

Front 36

Where does the myogenic repsonse occur in the nephron and why is it so important? ***TEST

Back 36

It maintains BF and BP in the face of drastic systematic changes that would otherwise damage the kidney.

***Seen only in the AFFERENT ARTERIOLES***

Front 37

What is tubuloglomerular feedback?

Back 37

1.Inc GFR is reflected as Inc NaCl sensed by the MD which will cause VC of afferent arteriole.

2.Dec GFR is reflected dec NaCl sensed by the MD which will release paracrines to VD afferent arteriole.

Front 38

2 key hormonal factors DECREASING RBF? what is the major outcome effect on GFR?

Back 38

1.RAAS: AngII VC BOTH afferent and efferent arterioles, more so the efferent.

2.SNS: VCs both.

**Although they DEC RBF, they have little change on GFR due to myogenic and tubuloglomerular feedback

Front 39

What is ADHs affect on RBF and GFR

Back 39

It does VC, but has little effect on RBF and GFR

Front 40

ANPs affect on RBF and GFR

Back 40

Causes afferent VD, Inc GFR and RBF. **Also inhibits the secretion of renin

Front 41

Why are prostaglandins so important in the kidney?

Back 41

They are protective against excessive vasoconstriction like the excess you might see with lots of SNS and ANG II.

**PGs will VD, preventing RAAS and SNS from causing renal ischemia

Front 42

When should you be worried about PGs in the kidneys?

Back 42

Pts Chronically on NSAIDs