Renal Toxicology Flashcards
1
Q
What are the main components of the Nephron ?
A
- proximal tubule
- loop of Henle
- distal tubule
- collecting duct
- Bowman’s capsule
2
Q
Why is the Proximal convoluted tubule the most common site of toxicant-induced renal injury?
A
- leaky epithelium
- P450 activity
- glomerular filtration toxicants concentrated in this area
3
Q
What does Aminoglycosides (gentamycin) do ?
A
causes acute proximal tubule necrosis in 10% of patients
4
Q
How much of cardiac output do the kidneys receive?
A
25%
5
Q
What might be concentrated in the kidney ?
A
Xenobiotics may be concentrated in the kidney as the kidneys are the main route of elimination
6
Q
How does Gentamycin cause nephrotoxicity ?
A
- filtered out of the glomerulus
- reabsorbed at the proximal tubule
- however it also binds to negatively charged phospholipids on the luminal side of the cell
- problem is because the plasma membrane is constantly being ingested
- so gentamicin is also endocytose into the cells
7
Q
What are the toxicological mechanisms of gentamicin ?
A
- binding to phospholipids alters membrane composition
- direct interaction of gentamicin with mitochondria
- accumulation of gentamicin in lysosomes
8
Q
Describe how selective toxicity to the proximal tubule can occur
A
- following filtration at glomerulus toxicants may be concentrated in this area
- reabsorption across brush-border membrane
- active transport & concentration
