Kidney Toxicity Flashcards
What is the role of the kidney
Excretion of wastes
Regulation of body homeostasis
Describe the kidney anatomy
Cortex, medulla, papilla
7 lobes structure
Why is the kidney susceptible to toxicity
1- High renal blood flow
2- Concentration of xenobiotics in tubular fluid due to glomerular filtration and water reabsorption
3- Bio transformation of parent compound to toxic metabolite
What are the toxic effects experienced in the glomerulus
Inflammatory response
Immune complexes
Blockages
What xenobiotics damage the proximal tubule
Antineoplastics
Halogenated hydrocarbons
Heavy metals
Antibiotics
What areas does amphotericin affect
Loop on Henle and distal tubule
What xenobiotics affect renal haemodynamics
Calcineurin inhibitors
NSAIDs
ACE inhibitors
ARBS
Describe the heavy metal mercury
Elemental environmental pollutant
Reduce Na+ reabsorption in Loop of Henle
Where does Hg+ act on the kidney
Selective to pars recta proximal tubular epithelial cells
How does Hg reach the kidney
Conjugated with GSH -> GS-HG-SG
Translocation to kidney in systemic circulation
Uptake into proximal tubule cell from tubular fluid
What happens when GS-HG-SG reaches the proximal tubule cell
Hg2+ is released and combines with SH on proteins
Depletes GSH = to mitochondrial stress
Inhibits membrane bound enzymes
Describe acute and severe Hg toxicity in the kidney
Acute: cellular necrosis in pars recta
Severe: tubular necrosis
How is cadmium excreted
Metallothionein complex
What is the role of metallothionein in the body
Synthesised in liver to protect tissues from Cd
Large number of SH groups
How does Cd toxicity happen
Cd-MT complex taken up by renal proximal tubule cell
Complex broken down by lysosomal enzymes
= free Cd that bind to Sh groups