Advertisement Upgrade to remove ads

Review glomerular filtration.


Review effect of change in relative arteriolar resistance.


Which renal arteriole constricts more upon sympathetic activation?

afferent arteriole

Which renal arteriole constricts more upon exposure to angiotensin 2?

efferent arteriole

Filtration fraction =


What percentage of the renal plasma flow is filtered?


What term describes the ability to maintain renal blood flow and glomerular filtration rate within narrow limits in the face of fluctuating MAP?

autoregulation; a

What are the 2 mechanisms of autoregulation?

myogenic mechanism

tubulo-glomerular feedback

Considering the myogenic response, what happens to vascular resistance if blood pressure increases?

vascular resistance increases

*maintains constant flow

Describe afferent arteriolar response to change in tension (transmural pressure) and its effects on GFR and RPF.

stretch-activated cation channels


Ca influx

vascular smooth muscle contraction

increased afferent arteriolar resistance

decreased GFR, decreased RPF

Name the 3 components of tubulo-glomerular feedback.




Describe the signal of the tubulo-glomerular feedback mechanism.

macula densa detects flow rate (NaCl concentration in tubular fluid)

Give an example of a mediator of the tubulo-glomerular feedback mechanism.


What is the action of the effector in the tubulo-glomerular feedback mechanism?

contraction of afferent arteriolar smooth muscle

Review tubulo-glomerular feedback.


Describe TGF in the case of increased GFR.

NKCC2 senses influx of Na, Cl

ATP released and converted to adenosine

adenosine binds receptor on afferent arteriole

[Ca]i increases

contraction of afferent vascular smooth muscle

Why is renin inhibited by the tubulo-glomerular feedback in case of increased GFR?

renin would promote unwanted water retention

Review regulation of RPF and GFR.


Describe TGF in the case of decreased GFR.

macula densa senses decreases in Na, Cl

NOS released

NO stimulates prostaglandin production

prostaglandin binds to Gs on afferent arteriole

increased RPF, GFR, renin

Do glucocorticoids promote vasoconstriction or vasodilation?


How do glucocorticoids promote vasoconstriction?

potentiate vasoconstriction action of norepinephrine

What is renal clearance?

the volume of plasma rendered free of a substance per unit time

Renal clearance ratio =

amount of substance in urine/concentration of substance in arterial plasma

Renal clearance =

(urine concentration of substance x urine flow)/arterial plasma concentration of substance

What are the units (general) of renal clearance?


Review suitable substance for estimation of GFR.


What is the purpose of renal clearance?

measure GFR

Name a very suitable substance for estimation of GFR.


Derive the equation for GFR using inulin.

rate of inulin filtration = rate of inulin excretion

volume of plasma cleared = glomerular filtration rate

GFR = (urine concentration of inulin x urine flow)/renal plasma concentration of inulin

What ion transporter is found on macula densa cells?


Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!



Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom


Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording