Renal Flashcards
What is the primary function of the renal system?
Blood filtration
What are the functional units of the nephron?
Renal corpuscle and the renal tubule
How much blood gets filtered in bowman’s space?
20%
Blood is filtered through which set of capillaries?
Glomerular capillaries
What are the parts of the renal tubule?
Proximal convoluted tubule, descending limb, loop of henle, ascending limb, distal convoluted tubule, cortical collecting duct and medullary collecting duct
Which nephrons go deep into the kidney medulla?
Juxtamedullary
What nephrons don’t have a loop of henle?
Cortical nephrons
Humans have mostly cortical or juxtamedullary nephrons?
Cortical
The salty inner portion of the kidney is referred to as what?
The medulla
The structure that wraps around the afferent arteriole is called what?
Juxtaglomerular apparatus
What is the function of the juxtaglomerular apparatus?
Senses renal blood pressure and secretes renin
What is reabsorption?
Flow from tubular fluid to blood
What is secretion?
Fluid moving from peritubular capillaries into renal tubule
What gets secreted?
Mostly water and glucose
Does secretion require a transporter?
Yes
Does coffee increase or decrease GFR?
Increase
GFR refers to what?
Volume flowing into bowman’s space per unit/time
Does the pressure in the glomerular capillaries favor or resist filtration?
Favors
Does the hydrostatic pressure in bowman’s space favor or resist filtration?
Resist
Is the osmotic force against or towards filtration?
Against
What are the three pressures involved in glomerular filtration?
Blood pressure in glomerular capillaries, hydrostatic pressure in bowman’s space, and osmotic force in the plasma
The net filtration pressure determines what?
GFR
What does the permeability of the corpuscular membrane influence?
GFR
Dilating the afferent arterioles and constricting the effect arterioles will do what to GFR?
Increase it
Dilating the efferent arterioles and constricting the afferent arterioles does what to the GFR?
Decreases it
What is the transport maximum?
Glucose concentration where the transporter is fully saturated
When does glucose excretion drastically pick up?
Right at tmax
Glucose in urine is a sign of what?
Diabetes
2/3rds of reabsorption happens in what part of the renal tubule?
Proximal convoluted tubule
What drives Na+ reabsorption out of the tubule?
Na/K pumps on proximal tubule epithelial cells
What is H+ secretion coupled to?
Na+ reabsorption
What keeps sodium concentration low in the proximal tubule epithelial cells?
Na/K pumps
The insertion of aquaporins in the collecting duct is stimulated by what hormone?
ADH
Inhibiting ADH results in what?
Very dilute urine
What is diabetes insipidus?
Issues with ADH synthesis and release
What increases cAMP in the collecting duct?
Adenylyl cyclase
The ascending limb is hypotonic to what else?
The interstitial fluid
What part of the renal tubule is isotonic to the interstitial fluid?
The descending limb
The descending limb is hyper or hypo osomotic to the ascending limb?
Hyperosomotic
What does hyperosmotic/hypertonic mean?
Mor concentrated with respect to a specific reference
What does hypotonic/hypoosmotic mean?
Less concentrated/more dilute with respect to a specific reference
If active transport is blocked in the renal tubule, what happens?
Loss of ability to concentrate urine
