Lecture 10 - Effects Of Drugs And Chemcials On The Nephron Part 2 Flashcards
How else apart from toxins can inflammation occur?
As a result of chronic conditions like diabetes
What does inflammation of the kidneys tubules do?
Leads to damage to the glomerular filtration barrier. Either due to edema or by infiltration of the inflammatory cells
What is edema?
It is swelling due to too much fluid
What happens when the filtration barrier loses its integrity due to inflammation?
Start to see large molecules like proteins appearing in the tubular fluid and into the urine
What happens to long term damage of the glomerular due to inflammation?
Get thickening of the Barrier as a result of fibrotic tissue (kidney fibrosis) which reduces the GFR rate
What could kidney fibrosis also cause?
Could become too thick and block the glomerular all together - meaning there is less space for the plasma to flow through capillaries - resulting in glomerulus death
What is an example for a toxin that gets taken by the podocytes?
Bucillamine - cells that wrap around the basal laminar - kill podocytes
What is the collecting duct surrounded by?
Tight junctions - water can not move in and out normally it has additional processes that help
What can amphotericin B do in the loop of henle?
It can form smaller pores in the apical membrane of the loop of henle.
What happens to amphotericin B as filtrate volume drops?
It increases rapidly
What happens when you start to see amphotericin B pores in the membrane? - Amphotericin treatment
causes leakages of K+ and Mhg2+ in the PCT, loss of the ability to excrete protons in the collecting cut
What is lithium usually given to people for?
Treatment for bipolar disorder. It interferes with the vasosupressin system
What does ADH (vasosupressin do)?
Inserts water pores in the collecting duct cells membrane to enable reabsorption of solute free water from the collecting duct
Where is ADH released from?
Pituitary
What happens when ADH binds to the collecting duct cells?
It triggers a second mechanism system which triggers the release of water pores from storage vesicles, aquaporin 2 can then exocytose the vesicle (now have a gate way for water to move)
What does lithium do that is bad for the collecting duct?
When it enters the collecting duct cell it directly interferes with the second messenger signal.
What are the 3 fates of tubular handling?
Filtered,
filtered then reabsorbed,
filtered and secreted
What is the filtered fate?
It is left untouched by the nephron - amount excreted = amount filtered e.g. inulin creatinine
What is the filtered and reabsorbed fate?
Amount excreted less then amount filtered e.g. glucose amino acids Na+
What is the filtered and secreted fate?
Amount excreted is more than amount filtered e.g. PAH drug molecular and metabolic end products
What converts chemicals from small to high MW?
Small lipid chemicals
How this process done? - small lipid molecules converting chemicals from small to high MW
2 step process:
1 - cytochromosomes p450, ADH and esterases introduce a functional group into the chemical
2 - transferases attach covalently a large water soluble molecule eg sulphate - creating conjugation
What is the down side of the process? - small lipid molecules converting small to high MW?
The activated chemical can turn a non toxic chemical into a toxic one. Introducing a functional group can make the compound more reactive and bind to proteins. Alterations the function
What is an example for heavy metal?
Mercury