Renal Metabolism

Question 1

During well-fed state, the major fuel for kidney is……m while during starvation it is……

Answer 1

Glucose
FAs & ketone bodies

Question 2

Describe the proportions of glucose reabsorption within the PCT

Answer 2

90% of filtered glucose is reabsorbed in the 1st part (S1) of the proximal tubule and is mediated by SGLT2, 10% is reabsorbed in distal (S2/S3) part of tubule & is mediated by SGLT1.

Question 3

Gluconeogeneisis occurs in……

Answer 3

Renal cortex

Question 4

Mention the importance of glutamine renal metabolism during starvation

Answer 4

The nitrogen if glutamine is eliminated as ammonium ions in urine and the carbon chain is utilized for gluconeogenesis.

Question 5

Mention enzymes involved in Miester cycleg-glutamyltranspeptidase

Answer 5

g-glutamyltranspeptidase, g-glutamylcysteinesynthetase, glutathione synthetase

Question 6

Why is cisplatin nephrotoxic?

Answer 6

As a result of the binding of cisplatin to glutathione and the subsequent metabolism of the cisplatin-glutathione and the subsequent metabolism of cisplatin by GGT-dependent pathway in PCT to cisplatin-cysteinyl-glycine conjugate which is nephrotoxin.

Question 7

Carnitine is synthesized from……

Answer 7

Lysine & methionine

Question 8

What is the cause of 1ry carnitine deficinecy

Answer 8

Caused by a defect in plasma membrane carnitine transporter in kidney & muscle resulting in inc urinary wasting and dec intracellular accumulation

Question 9

GR: Preterm neonates are at risk for developing carnitine deficiency

Answer 9

Bec they have impaired reabsorption of carnitine at the level of the PCT

Question 10

What is the effect of CRF on carnitine?

Answer 10

Impair biosynthesis of carnitine besides losing it in hemodialysis

Question 11

Acquired carnitine def can be caused by the drug……

Answer 11

Valproate

Question 12

Symptoms of caritine def include……

Answer 12

Muscular weakness, heart affection due to hypoglycemia

Question 13

Inc NH4+ production is associated with…….

Answer 13

High protein diet, prolonged fasting, overpoduction of normal metabolic acids as lactate, acetoacetate, b-hydroxybutyrate

Question 14

Kidney are responsible for degradation of………(hormones)

Answer 14

Insulin & PTH

Question 15

Normal glucose output is….., polyuria is….., oliguria is….., anuria is…….

Answer 15

1.5-2 L/day
More than 2L/day
Less than 0.5 L/day
Less than 0.1L/day

Question 16

……..alters pores, amounts & dispositions of negatively charged macromolecules.

Answer 16

Glomerulonephritis