Renal Processing of Urea and Glucose Flashcards Preview

Urinary Exam 1 > Renal Processing of Urea and Glucose > Flashcards

Flashcards in Renal Processing of Urea and Glucose Deck (27):
1

Where are amino acids absorbed?

PCT

2

How is urea reabsorbed in the PCT?

Dragged with water

3

Where is urea secreted?

Into the thin portions of the loop of Henle

4

What secretes urea into the thin loops?

UT-A2 (urea transporter A2)

5

What uptakes AA in the PCT?

Solute transporter carriers (SLC)

6

Normal BUN levels?

7-18 mg/dL

7

What does urea cause in the medullary interstitial space?

Reabsorption of water

8

What affect does ADH/AVP have?

Causes UT-A1 to reabsorb urea from the collecting duct in order to maintain a gradient in the medulla between collecting ducts and the thin ascending loop to draw water out of the tubules

9

What moves urea across the collecting ducts membranes?

Apical: UT-A1
Basolateral: UT-A3

10

What secondary messenger is used by ADH/AVP to activate UT-A1?

cAMP

11

What absorbs glucose across the PCT apical and basolateral membrane?

Apical: SGLT (sodium glucose)
Basolateral: GLUT 1/2

12

What creates the gradient for sodium to be used in the apical SGLT?

Na/K ATPase

13

What can occur in excess glucose concentration in the PCT?

SGLT can become oversaturated

14

When does splay occur?

When SGLT are oversaturated

15

Why is splay a curve and not a straight line?

Due to the many SGLT receptors with different glucose tubular maximums in the various nephrons

16

What does SLC1A1 code for?

Excitatory amino-acid transporter 3 (EAAT3)

17

What are EAAT3 also known as?

High affinity glutamate transporters

18

What drives AA transport?

The negative cell charge

19

Where are oligopeptides absorbed?

PCT
DCT

20

What absorbs oligopeptides in the PCT and DCT respectively?

PCT: PepT1
DCT: PepT2

21

PepT1 vs PepT2:

PepT1: high capacity low affinity
PepT2: low capacity high affinity

22

What is needed for oligopeptides to be absorbed?

Sodium

23

General mechanism of protein reabsorption?

Bind to receptor then endocytosed through clathrin coated pit to lysosomes and digested

24

What takes up albumin from the PCT?

Megalin
Cubulin

25

What transports carboxylates on apical?

Na-dependent mono-di-tri-carboxylate transporters

26

What transports dicarboxylates on the basolateral side?

OAT1 and OAT3

27

How does OAT work?

Pumps dicarboxylates across the basolateral for an organic anion into the cell