A&P Meat and potatoes Flashcards
-synthesize, store, release renin
-act as mechanoreceptors that sense blood pressure
-enlarged smooth muscles cells of arteriole
granular cells (juxtaglomerular/JG cells
-chemoreceptors that sense NaCl content of filtrate
-tall closely packed cells of ascending loop of Henle
Macula densa
the filtration membrane consist of what 3 things
- fenestrated endothelium of the glomerular capillaries
- Visceral membrane of the glomerular capsule(podocytes with foot processes and filtration)
- Gel-like basement membrane (fused basal laminae of the two other layers)
the filtration membrane’s, _________charged basement membrane repels large anions such as ______ ______.
negatively charged basement membrane repels large anions such as plasma proteins
The basement membranes has a negative charge. What does this repel?
negative proteins
Name the three major renal processes?
Glomerular filtration
tubular reabsorption
tubular secretion
the net filtration pressure is determined by ?
3 things
- glomerular hydrostatic pressure
- colloid osmotic pressure of glomerular blood
- Capsular hydrostatic pressure
GFR is governed by what three things?
(physiological)
- total surface area available for filtration
- filtration membrane permeability
- net filtration pressure
GFR is tightly controlled by what two types of mechanisms
- intrinsic control (auto regulation) act locally within kidney “prostanoids”
- extrinsic controls (nervous & endocrine that maintain blood pressure, but affect kidney function)
two types of renal auto regulation that control GFR are ?
not prostanoids and hormones
two types of renal auto regulation that control GFR are ?
- myogenic mechanism
- tubuloglomerular feedback mechanism
Myogenic mechanism maintains GFR by:
if BP is high?
if BP is Low?
- if BP is high, afferent arterioles constrict which helps maintain GFR and protect glomeruli from damaging
- if BP is low afferents arterioles constrict to help maintain normal GFR
in regards to intrinsic control of GFR regulated by tubuloglomerular feedback mechanism:
- the macula densa cells of the JGA respond to increased ______by releasing ______causing vasoconstriction of the afferent arteriole thereby decreasing ____.
- gives the PCT time to reabsorb more NaCl
- increased NaCl
- ATP
- decreasing GFR
under normal conditions at rest renal blood vessels are dilated and auto regulation mechanism controlled by _______ _______ _______ prevails.
sympathetic nervous system
in regards to sympathetic nervous system control of renal blood flow and filtration:
In times of extreme stress ______and ______ are released causing constriction of the afferent arterioles, inhibiting filtration and release of ______
norepinephrine
epinephrine
renin
in regards to the kidney:
- norepinephrine and epinephrine bind to beta 1 causing ______.
- norepinephrine and epinephrine bind to alpha 1 causing _______.
- which results in ______.
- release of renin
- vasoconstriction
- decreased GFR and reabsorb more water
When renin is released from the granular cells of the JGA it bust of a cascade. Tell me about.
- angiotensin (a plasma globulin)
- cleaved by renin (enzyme)
- kapow we got some angiotensin 1
-ACE (angiotensin converting enzyme)
-angiotensin 2
-aldosterone
the effects of angiotensin 2 are:
1.
2.
3.
1-constricts arteriolar smooth muscle-increases MAP
2-stimulates Na reabsorption via direct action on renal tubules and release of aldosterone from adrenal cortex
- Stimulates the hypothalamus to release ADH and activates the thirst center
- constricts efferent arterioles decreasing peritubular capillary hydrostatic pressure increasing fluid reabsorption
- causes glomerular mesangial cells to contract decreasing surface area for filtration
angiotensin’s main overall function is to maintain ?
maintain patient volume status in times of stress
Three triggers that cause release of Angiotensin by granular cells to maintain systemic blood pressure.
“please know all three”, (Captain Frida 2021)
- -reduced stretch (baroceptor) of granular cells (MAP below 80) “decreased systemic BP”
- -stimulation of granular cells by macula densa cells
- -stimulation of granular cells via B1 (norepi or epi) adrenergic receptors by renal nerves
“because cautious with renal patients, patients who’s lab indicate renal damage, or some one taking NSAIDS because vasoconstriction by norepi and angiotension 2 might be counteracted by________.
autacoids
prostaglandin E2 (PGI 2)
_____ _____ makes up ___% of nephrons, almost entirely in the _____
cortical nephrons
85%
cortex
vasopressin binding to A1 releases ___causing increase of ______ _____ by acting on the collecting duct via _______.
ADH
water reabsorption
aquaporins
the majority of sodium is reabsorbed where?
straight proximal tubule
most water reabsorption take place where?
proximal convuluted tubule
name two hormones that regulate water reabsorption?
ADH
aldosterone (via ion regulation)
most sodium is reabsorbed via the action of the____.
(primary active transport out of the tubule in the basolateral membrane)
NaK ATPase pump
the most abundant cation in filtrate is?
sodium
the reabsorption of _____provides the energy and the means of reabsorbing most other substances
sodium
organic nutrients are reabsorbed via
secondary active transport (atp and co-transporters)
______is a selective transepithelial process in which all organic nutrients are reabsorbed and water and ion reabsorption are hormonally regulated
tubular reabsorption
the proximal convoluted tubule reabsorbs
1.
2.
3.
4.
65% of Na and water
all nutrients
ions
small proteins
the descending loop of Henle absorbs
water
the ascending loop of Henle reabsorbs
Na, K, Cl
the descending loop of Henle is thin and absorbs water while the ascending loop of Henle is thicker has ____ and reabsorbs ions.
pumps
the distal convoluted tubule and collecting duct are ______regulated and reabsorb ____, ____, and___.
Ca
water
Na
Calcium reabsorption is regulated by what hormone?
parathyroid hormone
water reabsorption is regulated by what hormone?
ADH
sodium reabsorption is regulated by what two hormone?
Aldosterone and ANP
what hormone targets collecting ducts (principal cells) and the DCT to promote synthesis of luminal Na and K channels and promotes synthesis of basolateral NaK ATPase
aldosterone
the mechanism in which we eliminate excess K, Hydrogen, creatine, organic acids and control blood PH by altering Hydrogen and bicarb in the urine
tubular secretion
what hormone plays a part in the elimination of K?
aldosterone
the countercurrent multiplier is ?
filtrate flow in the loop of Henle
the concurrent exchanger is ?
blood flow in the vasa recta
the biggest player in regards to concentrating urine?
ADH
the role of the countercurrent mechanism is to?
the role of the countercurrent mechanism is to?
- establish an osmotic gradient from renal cortex through the medulla
- allows kidneys to vary urine concentration
concurrent multiplier:
the _____is freely permable to water which passes out the filtrate into the hyperosmotic medullary interstitial fluid
descending loop of Henle
the descending loop of henle is permeable to ____and impermeable to ______which results in increasingly concentrated filtrate osmolarity of 300-1200.
the ascending loop of henle is permeable to ____and impermeable to ______ which results in increasingly dilute filtrate osmolarity of 100
the descending loop of henle is permeable to water and impermeable to NaCl which results in increasingly concentrated filtrate osmolarity of 300-1200.
the ascending loop of henle is permeable to NaCl and impermeable to water which results in increasingly dilute filtrate osmolarity of 100
______contributes to the high osmolality in the medulla
urea
delivers blood to medullary tissues
vasa recta
slide 27 in red
- has a short loop of Henle and glomerulus further from corticomedullary junction
- efferent arteriole supplies peritubular capillaries
cortical nephron
slide 27 in red
- has a long loop of henle and glomerulus closer to the corticomedullary junctions
- efferent arteriole supplies vasa recta
juxtamedullary nephron
filtrate is diluted in the _______by pulling sodium out with pumps.
ascending loop of Henley
in the absence of ____dilute filtrate continues into the renal pelvis as dilute urine
ADH
freely permeable to water which passes out of the filtrate into the hyperosmotic medullary interstitial fluid
descending loop of Henle
where is?
-filtrate osmolality decreases to 100 mOsm
ascending limb of the loop of henle
Na and Cl are passively reabsorbed in the ______ segment and actively reabsorbed in the _______ segment of ascending loop of Henle.
thin
thick
as filtrate passes through the descending loop of Henle _____ is removed and _____ _____ goes into the filtrate resulting in the osmolarity _______ and the filtrate becoming more ______.
as filtrate passes through the descending loop of Henle water is removed and sodium chloride goes into the filtrate resulting in the osmolarity increasing and the filtrate becoming more concentrated.
as filtrate passes through the ascending loop of Henle water is ______ and _____ _______ goes out of the filtrate resulting in the osmolarity ______ and the filtrate becoming more ______.
as filtrate passes through the ascending loop of Henle water is absorbed and sodium chloride goes out of the filtrate resulting in the osmolarity decreasing and the filtrate becoming more dilute.
-highly permeable to H20, sluggish blood flow, letting time for reabsorption of NaCl and water
- maintains osmotic gradient
- delivers blood to medullary tissues
- prevents rapid removal of salt by removing reabsorbed H20
vasa recta
_______triggers reabsorption of H20 in the collecting ducts
ADH
_______triggers reabsorption of H20 in the collecting ducts
ADH
formation of concentrated urine depends on the medullary _____gradient and _____.
osmotic
ADH
