Renal Physiology Part 3 Flashcards
(24 cards)
What are the three types of cells in the juxtaglomerular apparatus?
1.Macula densa
2. Juxtaglomerular (granular) cells
3. Extraglomerular mesangial cells
What is the primary function of extraglomerular mesangial cells?
They play a role in immune response and regulation of glomerular filtration.
How do extraglomerular mesangial cells help maintain the glomerular filtration barrier?
By phagocytosing and clearing immune complexes and debris.
What is the primary function of extraglomerular mesangial cells?
They play a role in immune response and regulation of glomerular filtration.
What is the formula for urinary excretion rate?
Urinary excretion rate = Filtration rate – Reabsorption rate + Secretion rate
Why is the clearance function of extraglomerular mesangial cells important?
It helps preserve the integrity of the glomerular filtration barrier and prevents damage.
What are the three main processes involved in urine formation?
- Glomerular filtration
- Reabsorption
- Secretion
Where does glomerular filtration occur?
In the glomerular capillaries inside Bowman’s capsule.
What is secretion in the context of urine formation?
The transfer of substances from the blood into the renal tubules.
What happens during reabsorption in the nephron?
Substances are reabsorbed from the renal tubules back into the blood.
What vessels are involved in bringing blood into and out of the glomerulus?
Afferent arteriole (in), Efferent arteriole (out)
Which capillaries are involved in reabsorption and secretion?
Peritubular capillaries
Where does urine formation begin?
It begins with the filtration of plasma from the glomerular capillaries into Bowman’s space.
What is glomerular filtrate?
A cell-free, protein-free filtrate containing all plasma substances in the same concentrations.
What is another name for glomerular filtrate?
Ultrafiltrate
Panel A, how is the substance handled by the kidney?
It is freely filtered, not reabsorbed or secreted; excretion rate = filtration rate (e.g., creatinine).
What processes follow glomerular filtration in urine formation?
Reabsorption and tubular secretion in the tubules and collecting ducts.
What is another name for glomerular filtrate?
Ultrafiltrate
What does an increase in blood creatinine indicate?
Kidney dysfunction or impaired filtration.
In Panel B, how is the substance handled?
It is freely filtered and partially reabsorbed; excretion rate = filtration rate – reabsorption rate (e.g., Na⁺, Cl⁻).
: In Panel C, what happens to the filtered substance?
It is completely reabsorbed, so nothing is excreted in the urine (e.g., glucose, amino acids).
What does an increase in blood creatinine indicate?
Kidney dysfunction or impaired filtration.
In Panel D, how is the substance handled?
It is freely filtered and secreted into the tubules, not reabsorbed; excretion rate = filtration rate + secretion rate (e.g., organic acids).
What is the purpose of secretion in the nephron?
To rapidly clear substances like organic acids from the blood and excrete them in urine.
