Renal Physiology 1 & 2 Flashcards
What are the major functions of the kidney? (6)
Endocrine functions
Metabolic functions: gluconeogenesis
pH regulation
Salt/ion homeostasis
Excretion of medication
Body water balance
The resting membrane potential is based on the what of cells?
K+ gradient inside and outside of cells - very important for neurons and cardiomyocytes (heart and brain function)
This is kidney disease/failure.
Hyperkalemia
This is a commonly used anaesthetic that is excreted by the kidneys after metabolism in the liver due to its fat soluble nature.
Lidocaine
This is a common painkiller excreted directly by the kidneys due to its high water solubility.
Aspirin
What’s the difference between lipophilic drugs and hydrophilic drugs? (in terms of excretion)
Lipophilic drugs need to be metabolised in the liver then filtered in the kidney.
Hydrophilic drugs can be directly filtered in the kidney and excreted in urine.
True or false. Total body water hardly remains constant.
False. It remains relatively constant, it must to maintain kidney function.
True or false. Urine output may be adjusted to ensure total body water is balanced.
True
How does the kidney regulate pH?
By reabsorbing and secreting bicarbonate and hydrogen ions.
Remember: even in the GI tract, when it comes to secretion of bicarbonate and hydrogen ions, it always boils down to pH regulation function.
True or false. Males have more body water than females.
True
What are the proportions of ECF (plasma + interstitial fluid) and ICF in the body?
2/3 ICF
1/3 ECF (1/5 plasma, 4/5 interstitial fluid)
This is defined as the total number of solute molecules in solution.
Osmolarity
This is defined as having the same amount of solute molecules per litre - same osmolarity.
Isosmotic
This is when there are less solute molecules per litre and there is a decrease in osmolarity (more water).
Hyposmotic
This is when there are more solute molecules per litre and there is an increase in osmolarity (less water).
Hyperosmotic
This occurs in the renal corpuscle. It is the process of moving plasma from the glomerular capillaries into the glomerular capsule.
Filtration
True or false. Water and solutes are filtered at a constant rate at the renal corpuscle.
True.
This is the process of moving solutes from the peritubular capillaries into the tubular fluid. It removes additional substances like waste products from the blood so that they’re excreted in the urine. (eg., metabolites, medications and toxins)
Secretion
Where does the secretion of metabolites, medication and toxins occur in the nephron?
Proximal tubule