Study sets, textbooks, questions
Upgrade to remove ads
Terms in this set (185)
What is the effect of parathyroid hormone on the early distal convoluted tubule (DCT)?
↑ Ca2+/Na+ exchange → ↑ Ca2+ reabsorption
How does angiotensin II promote contraction alkalosis?
Increased Na+/H+ activity on the proximal convoluted tubules → increased reabsorption of HCO3-, Na+, and H2O
What is the formula for secretion rate?
Amount excreted - Amount filtered
The body's extracellular fluid is mainly composed of what electrolytes?
HCO3-, Na+, Cl-, albumin
When plasma glucose levels exceed 200 mg/dL, what finding may be seen on urinalysis?
Glucosuria (proximal tubule glucose reabsorption threshold is 200 mg/dL)
What hormone released by the kidneys induces red blood cell proliferation in bone marrow?
What are the main effects of aldosterone on the electrolytes of the kidneys?
Increased secretion of K+ and H+ and increased reabsorption of Na+
Aldosterone binding to receptors on α-intercalated cells increases activity of which transporter?
H+ ATPase (↑ H+ secretion)
What adverse effect can erythropoietin supplementation cause?
How do angiotensin-converting enzyme (ACE) inhibitors increase bradykinin levels?
ACE normally breaks down bradykinin; ACE inhibitors prevent bradykinin degradation → increase in bradykinin
Name 4 things that can cause hypokalemia by promoting a shift of K+ into cells.
β-Adrenergic agonists, alkalosis, hypo-osmolarity, and insulin (insulin shifts K+ into cells)
What primary acid-base disturbance is present when arterial pH is < 7.35 and PCO2 is > 44 mm Hg?
What are the 3 main functions of aldosterone?
ECF volume and Na+ content regulation; release is increased in response to low blood volume; causes increased K+ excretion during hyperkalemic states
What acid-base imbalance is seen with renal tubular acidoses?
Normal anion gap (hyperchloremic) metabolic acidosis
Describe the PCO2 status, HCO3- status, and compensatory response of respiratory acidosis.
Hypoventilation → increased PCO2 (primary disturbance) → delayed compensatory increase in renal reabsorption of HCO3-
What is the tonicity of the reabsorption of glucose, amino acids, HCO3-, Na+, Cl-, K+, PO43-, and H2O in the proximal tubule?
What is the mechanism by which aldosterone influences electrolyte management within renal collecting tubules?
Aldosterone → mineralocorticoid receptors (both principal cells and α-intercalated cells) → mRNA → protein synthesis
What primary acid-base disturbance is present when arterial pH is > 7.45 and HCO3- is > 28 mEq/L?
What fraction of total body water (TBW) is extracellular vs intracellular?
TBW = 1/3 extracellular, 2/3 intracellular
What ECG findings are associated with hypokalemia?
Arrhythmias, U waves and flattened T waves
How does syndrome of inappropriate antidiuretic hormone secretion (SIADH) affect blood pressure, plasma renin, aldosterone, serum Mg2+, and urine Ca2+?
Blood pressure may be unaffected or increased; plasma renin and aldosterone are decreased; serum Mg2+ and urine Ca2+ are unaffected
What is the mechanism behind the metabolic acidosis in renal tubular acidosis type 1?
α-Intercalated cells are unable to secrete H+, impairing the formation of HCO3- and leading to the development of a metabolic acidosis
Which part of the kidney is most susceptible to hypoxia?
Renal medulla (receives less blood flow than renal cortex)
What is the formula for estimating renal blood flow (RBF) if the renal plasma flow (RPF) is known?
RBF = RPF ÷ (1 - hematocrit)
What percentage of Na+ and water is reabsorbed in the early proximal convoluted tubule (PCT)?
In a patient, the measured PCO2 is less than the predicted PCO2. What does this indicate?
There is a concomitant respiratory alkalosis
Which nephron cells secrete dopamine and what is the effect?
Proximal convoluted tubule cells to promote natriuresis
What primary acid-base disturbance is present when arterial pH is < 7.35 and HCO3- is < 20 mEq/L?
What changes in the concentration of inulin occur in the distal proximal convoluted tubule?
The concentration of inulin ↑ due to ↑ H2O reabsorption along the tubule (raw amount of inulin remains constant)
How do prostaglandins affect the glomerular filtration rate (GFR) and renal plasma flow (RPF)?
Prostaglandins → dilate afferent arteriole → ↑ GFR and RPF to keep the filtration fraction (FF) constant
Under what condition will the tubular fluid-to-plasma (TF/P) ratio of a solute be > 1?
When the solute is reabsorbed less quickly than H2O or when the solute is secreted
Which cells secrete renin?
Which arteries supply the distal ureter?
Superior vesical and internal iliac arteries
The slope of [Na+] along the tubular to fluid/plasma (TF/P) curve remains constant along the length of the proximal tubule. Is it being secreted, reabsorbed, or neither?
Reabsorbed; rate is constant because solute and water are being reabsorbed at the same rate
What is the pathophysiology that results in metabolic and electrolyte derangement in the syndrome of apparent mineralocorticoid excess?
11β-Hydroxysteroid dehydrogenase deficiency → ↑ cortisol → ↑ mineralocorticoid receptor activity (cortisol tries to be the same as aldosterone)
What acid-base imbalance is seen with pH 7.30, HCO3- 12, PCO2 25, Na+ 142, Cl- 120?
Metabolic acidosis with normal anion gap
How is urinary reflux prevented physiologically?
When the bladder contracts, it compresses the intravesical ureter and prevents urine reflux
In terms of ion processing, what are the 2 main functions of β-intercalated cells in the renal collecting tubule?
They secrete HCO3- into the urine in exchange for Cl- and promote H+ release into the blood
Which substances have a tubular fluid-to-plasma (TF/P) ratio ≈ 1?
Na+ and K+
Which parts of the kidney are directly and indirectly affected by angiotensin II?
Efferent arteriole, proximal convoluted tubule, ascending loop of Henle, distal convoluted tubule
Which 3 ions are actively taken up from the urine by the thick ascending loop of Henle?
Cl-, Na+, and K+
What symptoms/signs can be seen in a patient with hypernatremia?
Stupor, irritability, coma
From which cells is angiotensin-converting enzyme (ACE) derived and what are its 2 primary functions?
Vascular endothelial cells in the lungs and kidneys; cleaves angiotensin I → angiotensin II and participates in bradykinin breakdown
What hormone inhibits the Na+/PO43- cotransporter in the early proximal convoluted tubule (PCT)?
Parathyroid hormone (normally ↑ phosphate excretion)
What happens to the osmolarity of urine as it passes through the early distal convoluted tubule (DCT)?
↑ Hypotonicity (dilute) due to membrane impermeability to water
In renal tubular acidosis type 2, what compensatory mechanism of the kidney may acidify the urine, and what is the net result on body acid-base status?
Urine can be acidified by α-intercalated cells in the collecting duct, but not enough to overcome ↑ HCO3- excretion in the proximal convoluted tubule; metabolic acidosis results
In a 70-kg patient, what percentage of the total blood volume is hematocrit (Hct)?
How do angiotensin-converting enzyme (ACE) inhibitors affect filtration fraction (FF)?
ACE inhibitors block angiotensin II → efferent arteriole constriction → ↓ FF (due to ↑ renal plasma flow and ↓ glomerular filtration rate)
What type of cell in the collecting tubule of a nephron is responsible for Na+/K+ exchange and the reabsorption of H2O?
The principal cell
What are the 3 common points of ureter obstruction?
Pelvic inlet, ureteropelvic junction, and ureterovesical junction
Under what condition will the tubular fluid-to-plasma (TF/P) ratio of a solute = 1?
When the solute is reabsorbed at the same rate as H2O
The glomerular slit diaphragm filters by what parameter?
By size, preventing molecules that are > 4-5 nm from entering
Which portion of the loop of Henle is impermeable to H2O?
Thick ascending portion and distal convoluted tubule (DCT)
What fraction of extracellular fluid (ECF) is plasma vs interstitial?
ECF = 1/4 plasma, 3/4 interstitial
Which layers of the glomerulus filter by preventing negatively charged molecules, such as albumin, from entering?
All 3 layers because all contain negatively charged glycoproteins
What effect would administration of nonsteroidal anti-inflammatory drugs (NSAIDs) have on patients with chronic kidney disease or low renal blood flow states?
Inhibition of prostaglandin synthesis by NSAIDs → constriction of afferent arterioles and decreased glomerular filtration rate → possible acute kidney injury
What is the effect of atrial natriuretic peptide on the kidney's glomerular filtration rate (GFR) and Na+ excretion?
Increased GFR and increased Na+ filtration without compensatory Na+ reabsorption in the distal nephron, resulting in net loss of Na+ and volume
What is a major difference between the actions of angiotensin II and atrial natriuretic peptide (ANP) on Na+ in the kidneys?
Angiotensin II increases Na+ reabsorption, whereas ANP increases Na+ filtration (which leads to increased loss of Na+ in urine)
What primary acid-base disturbance is present when arterial pH is < 7.35, HCO3- is < 20 mEq/L, and the anion gap is > 12 mEq/L?
Increased anion gap metabolic acidosis
Unlike inulin, why does creatinine clearance slightly overestimate the glomerular filtration rate?
Creatinine is moderately secreted by renal tubules
What effect do prostaglandins have on afferent arterioles?
Prostaglandins Dilate Afferent arterioles (PDA)
How do you determine if a metabolic acidosis with a measured PCO2 of 26 and HCO3- of 8 is a pure anion gap metabolic acidosis?
With the Winters formula: predicted PCO2 = 1.5  + 8 ± 2, or 22 (not within ± 2 of 26); in this case, respiratory acidosis is present in addition to an increased anion gap
In terms of filtration in the glomerulus, what is the equation for filtered load?
Filtered load (mg/min) = Glomerular filtration rate (mL/min) × Plasma concentration (mg/mL)
Increased activity of which 2 transporters occurs when aldosterone binds to principal cells?
Na+/K+ ATPase and ENaC
What ECG findings are associated with hyperkalemia?
Arrhythmias, peaked T waves, widened QRS complexes
What is the filtered load if glomerular filtration rate (GFR) is 125 mL/min and plasma concentration is 10 mg/mL?
Filtered load = GFR × plasma concentration = (125 mL/min) × (10 mg/mL) = 1250 mg/min
What effects does parathyroid hormone have on calcium and phosphate at the distal and proximal convoluted tubules, respectively?
Proximal convoluted tubule (PCT): ↓ PO43- reabsorption; distal convoluted tubule (DCT): ↑ Ca2+ reabsorption; ↑ 1,25-(OH)2 D3 production
In response to what physiologic changes is parathyroid hormone secreted?
Decrease in plasma [Ca2+], increase in plasma [PO43-], or decrease in plasma 1,25-(OH)2D3
Why can pregnant women have glucosuria but not have diabetes?
Normal pregnancy is associated with ↑ GFR → ↑ filtration → ↓ glucose threshold → glucosuria at normal plasma glucose levels
What is the primary acid-base disturbance when arterial pH is > 7.45 and PCO2 is > 40 mm Hg?
Which segment of the nephron in the renal medulla is most permeable to salts?
The ascending limb of the loop of Henle
In addition to water, antidiuretic hormone (ADH) stimulates reabsorption of what molecule within collecting ducts?
Urea (maximizes corticopapillary osmotic gradient)
The clearance of which substance best estimates renal plasma flow?
What clinical findings are associated with low phosphate levels?
Bone loss, rickets in children, and osteomalacia in adults
In the collecting tubule, which ion diffuses from the urine into the blood passively?
Cl- (via α-intercalated cells)
In terms of ion processing, what are the 2 main functions of α-intercalated cells in the renal collecting tubule?
Secrete H+ into the urine in exchange for K+ and promote HCO3- release into the blood in exchange for Cl-
If the glomerular filtration rate (GFR) is 125 mL/min, and renal plasma flow (RPF) is 500 mL/min, what is the filtration fraction (FF)?
FF = GFR ÷ RPF = (125 mL/min) ÷ (500 mL/min) = 0.25 = 25%
How do the ureters run in relation to the common iliac artery?
Water (ureters) flows over the common iliac artery (and under the bridge [uterine artery or vas deferens])
What is the formula for reabsorption rate?
Filtered substance - Excreted substance
What peptide involved in the renal-angiotensin-aldosterone system promotes natriuresis and dilates renal afferent arterioles?
Atrial natriuretic peptide (ANP)
Angiotensin II stimulates release of aldosterone from where?
The adrenal glands
What polysaccharide is contained in the renal glomerular basement membrane (GBM)?
What is the active form of vitamin D that is produced in the kidneys?
1,25-(OH)2 Vitamin D3 (calcitriol)
What effect does aldosterone have on cellular transports in principal cells of the renal collecting tubule?
Increases apical K+ conductance, Na+/K+ pump activity, and epithelial sodium channel (ENaC) activity → lumen negativity → increased K+ secretion
What differentiates the left renal vein from the right renal vein?
Left renal vein receives 2 additional veins: the left gonadal vein and the left suprarenal vein
List 3 causes of renal tubular acidosis type 2
Carbonic anhydrase inhibitors, multiple myeloma, Fanconi syndrome
What are the 3 types of cellular structures that make up the juxtaglomerular apparatus?
Juxtaglomerular cells, mesangial cells, macula densa
The body's intracellular fluid is mainly composed of what electrolytes?
Mg2+, K+, and organic phosphates (such as ATP)
What is the unit of measurement for glomerular filtration rate?
Volume over time, usually measured in milliliters per minute (mL/min)
What effect does dopamine have on renal blood flow (RBF) and glomerular filtration rate (GFR) at low doses?
Dilates afferent/efferent arterioles and interlobular arteries, which leads to increased RBF but has minor or no effect on GFR
Antidiuretic hormone (ADH or vasopressin) primarily acts on which part of the kidney?
Principal cells of collecting duct
How does urine osmolarity change in the thin descending loop of Henle?
Becomes hypertonic because the thin descending loop is impermeable to Na+ while passively reabsorbing H2O
What is the function of the macula densa in the jusxtaglomerular apparatus?
Senses NaCl located at the distal convoluted tubule (DCT)
What effect will decreased NaCl delivery to the distal convoluted tubule (DCT) have on the macula densa cells and juxtaglomerular apparatus?
Increased release of renin, resulting in efferent arteriole vasoconstriction, which leads to an increase in the glomerular filtration rate (GFR)
What are the effects of renin release by the juxtaglomerular cells on blood pressure?
Activation of the renin-angiotensin-aldosterone system (RAAS) → ↑ blood pressure → maintenance of glomerular filtration rate (GFR)
Describe the effects of reduced plasma protein concentration on glomerular filtration rate (GFR), renal plasma flow (RPF), and filtration fraction (FF).
Both GFR and FF ↑; RPF not affected
The clearance of which substance can be used to estimate the glomerular filtration rate?
What is the initial acid-base imbalance seen with aspirin (ie, salicylate) overdose?
What are the possible causes of a metabolic acidosis with an anion gap?
Methanol (formic acid), Uremia, Diabetic ketoacidosis, Propylene glycol, Iron tablets or INH, Lactic acidosis, Ethylene glycol (oxalic acid), Salicylates (late) (MUDPILES)
How does aldosterone secretion from the adrenal glands create favorable conditions for salt retention?
Acts on renal principal cells → ↑ K+ conductance, ↑ Na+/K+ ATPase, and ↑ epithelial sodium channel (ENaC) activity → ↑ Na+ reabsorption and ↑ K+ secretion
How does angiotensin II affect the efferent arterioles?
Angiotensin II Constricts Efferent arteriole (ACE)
Besides hypomagnesemia, what other electrolyte disturbances can occur with a Mg2+ level < 1.0 mEq/L?
Hypokalemia and hypocalcemia
What effect do insulin and β-adrenergic agonists have on K+ and why?
They increase Na+/K+ ATPase activity to increase K+
How would angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs) lead to renal tubular acidosis (RTA)?
Decreased production of aldosterone leads to RTA 4
Reabsorption of which electrolyte drives H2O reabsorption, nearly matching total osmolarity throughout the length of the proximal convuluted tubule?
How do β-blockers lower renin levels?
β-Blockers inhibit β1-receptors of the juxtaglomerular apparatus, resulting in decreased release of renin
In performing a workup for acid-base status on a patient, what is the first test that should be ordered?
An arterial blood gas pH; a pH < 7.35 indicates acidemia, whereas a pH > 7.45 indicates alkalemia
Which substances have a tubular fluid-to-plasma (TF/P) ratio < 1?
HCO3-, amino acids, and glucose
What symptoms/signs can be seen in a patient with hyponatremia?
Malaise, stupor, nausea, seizures, coma
Which arteries supply the proximal ureter?
Calculate the secretion rate when the filtered load is 100 mg/min, and the excretion rate is 200 mg/min.
Secretion rate = Excreted - Filtered = (200 mg/min) - (100 mg/min) = 100 mg/min
Which hormone is secreted by the kidneys in response to hypoxia?
Erythropoietin; released by the interstitial cells of the renal peritubular capillaries
What is the 60-40-20 rule (percentage of body weight) for the average person?
60% total body water, 40% intracellular fluid, and 20% extracellular fluid
What are 3 conditions that lead to increased plasma renin levels?
Decreased blood pressure detected by renal baroreceptors in afferent arteriole; decreased delivery of NaCl to macula densa cells; increased renal sympathetic tone (β1 effect)
What is the net effect of angiotensin II when it acts on the kidney?
Preserves renal function by increasing the filtration fraction in low-volume states and maintaining circulating volume by increasing Na+ reabsorption
What is the effect of angiotensin II on the proximal convoluted tubule (PCT)?
↑ Na+/H+ exchange → ↑ Na+, H2O, and HCO3- reabsorption (permits contraction alkalosis)
Describe the PCO2 status, HCO3- status, and compensatory response of respiratory alkalosis
Increased ventilation leads to decreased PCO2 (primary disturbance) with delayed compensatory renal HCO3- excretion into urine
Which acid-base abnormality would you expect with hyperventilation?
Respiratory alkalosis, lowering PCO2 to < 36 mm Hg and raising pH to > 7.45
Why is the left kidney removed from the donor during living donor transplantation?
The left kidney is removed from the donor because it has a longer renal vein than the right kidney
In which fluid compartment is the concentration of K+ higher?
Intracellular (HIKIN': HIgh K+INtracellularly)
How does angiotensin (AT) II affect the glomerular filtration rate (GFR) and the filtration fraction (FF)?
AT II causes constriction of efferent arterioles, resulting in increased GFR and increased FF with compensatory Na+ reabsorption in the proximal and distal nephron
Which substances have a tubular fluid-to-plasma (TF/P) ratio > inulin?
Para-aminohippuric acid (PAH) and creatinine
What is the tubular fluid-to-plasma (TF/P) ratio for amino acids and glucose compared with inulin and why?
Low due to net reabsorption in the proximal convoluted tubule
What would you expect the serum K+ level to be in a patient who overdoses on insulin?
Low because insulin drives K+ into cells, causing hypokalemia (insulin shifts K+ into cells)
What indirectly induces the paracellular absorption of Mg2+ and Ca2+ at the thick ascending loop of Henle?
Positive lumen potential generated by K+ backleak
Why are patients with chronic kidney disease often anemic?
Erythropoietin release is compromised in chronic kidney disease
What are the major signs/symptoms of hypermagnesemia?
Diminished deep tendon reflexes, hypotension, lethargy, hypocalcemia, bradycardia, cardiac arrest
How does the body compensate for metabolic acidoses and alkaloses?
By adjusting the breathing rate to expel (in the case of acidosis) or retain (in the case of alkalosis) carbon dioxide
What percentage of cardiac output is typically allocated to renal blood flow?
20%-25% (remains constant due to autoregulation)
What is the function of the glomerular filtration barrier?
It filters plasma according to size and charge
What mechanisms or disease states can lead to respiratory acidosis?
Hypoventilation; due to airway obstruction, acute or chronic lung disease, sedatives, opioids, weakened respiratory muscles
What is the expected renal filtration fraction in a healthy individual?
Describe the effects of dehydration on glomerular filtration rate (GFR), renal plasma flow (RPF), and filtration fraction (FF).
GFR ↓, RPF ↓↓, FF ↑
How do the concentrations of Na+ and Cl- compare as they move distally through the proximal convoluted tubule (PCT)?
Distally, Cl- concentration plateaus & parallels Na+; proximally, relative concentration of Cl- ↑ vs Na+ (implies that Cl- & Na+ absorption are parallel in the distal PCT)
Where in the nephron does the conversion of 25-OH D3 to 1,25-(OH)2 D3 take place?
Proximal convoluted tubule
What is the normal value for an anion gap?
Normal value is 8-12 mEq/L
If a patient's renal clearance is below the glomerular filtration rate, is there net tubular reabsorption or secretion?
Net reabsorption and/or not freely filtered
What enzyme from the kidneys is activated by parathyroid hormone?
Which arteries supply the middle ureter?
Gonadal artery, aorta, common and internal iliac arteries
On what segment of the nephron does aldosterone primarily exert its effects?
Describe the PCO2 status, HCO3- status, and compensatory response of metabolic alkalosis.
Increased HCO3- (primary disturbance) leads to immediate compensatory hypoventilation and increased PCO2
Juxtaglomerular cells in the juxtaglomerular apparatus are modified smooth muscle cells of what arteriole of the glomerular vasculature?
The afferent arteriole
What is the formula for calculating the filtration fraction (FF) for a given molecule?
Glomerular filtration rate (GFR) / renal plasma flow (RPF)
How does angiotensin II affect renal plasma flow (RPF), glomerular filtration rate (GFR), and filtration fraction (FF)?
↓ RPF, ↑ GFR and FF
What is the normal range for serum osmolality?
275-295 mOsm/kg H2O
Describe the symptoms/signs of hypocalcemia.
Seizures, tetany, spasm (eg, Trousseau sign), twitching (eg, Chvostek sign), and QT prolongation
In what way is the effective renal plasma flow (eRPF) a flawed estimate of renal plasma flow (RPF)?
eRPF slightly underestimates RPF
What are the effects of 1,25-(OH)2 vitamin D3 in the gut in response to the action of parathyroid hormone in the kidneys?
Increased absorption of Ca2+ and PO43-
In the early distal convoluted tubule (DCT), which ion(s) diffuse from the urine into the blood as a result of transporter activity?
Na+ and Cl-
Describe how changes in serum NaCl lead to renin release.
Decreased delivery of NaCl to the macula densa → renin secretion from the juxtaglomerular apparatus
What is the value for the normal glomerular filtration rate (GFR)?
≈ 100 mL/min
What type of collagen is mainly present in the glomerular basement membrane?
Type IV collagen
Which portion of the loop of Henle is permeable to H2O?
Thin descending portion and proximal convoluted tubule (PCT)
What is renal clearance?
The volume of plasma from which a substance is completely cleared in the urine per unit time
Besides maintaining blood pressure and blood volume, what are 2 additional physiologic functions of angiotensin II?
Helps regulate baroreceptor function and limits reflex bradycardia (counteracts angiotensin II's pressor effects)
What 2 medications lead to a metabolic alkalosis?
Loop diuretics and antacids
What 2 cell types in the nephron does aldosterone act on?
Principal cells and α-intercalated cells
In which organ is angiotensinogen of the renin-angiotensin-aldosterone system pathway first synthesized?
Which substance can be used to accurately calculate the glomerular filtration rate and why?
Inulin, as it is freely filtered and neither secreted nor reabsorbed
What percentage of Na+ is reabsorbed in the collecting tubule?
What does antidiuretic hormone (ADH) primarily regulate and by what mechanism?
Serum osmolality via reabsorption of water in the collecting ducts
Aldosterone is secreted in response to what physiologic changes?
Reduced blood volume (via angiotensin II) and increased plasma [K+]
On which cell type in the nephron does antidiuretic hormone (ADH) exert its function?
Principal cells of collecting ducts → ↑ aquaporins → ↑ water reabsorption
What do podocyte foot processes interpose with?
Glomerular basement membrane
What percentage of Na+ is reabsorbed in the thick ascending loop of Henle?
What is the course of the ureters?
Renal pelvis → travel under gonadal arteries → over common iliac artery → uterine artery/vas deferens
What percentage of Na+ is reabsorbed in the early distal convoluted tubule (DCT)?
What are clinical manifestations of hypercalcemia?
Stones (renal), bones (pain), groans (abdominal pain), thrones (increased urinary frequency), psychiatric overtones (anxiety, altered mental status)
What hormones derived from cardiac tissue inhibit the renin-angiotensin-aldosterone system in response to volume overload?
Atrial natriuretic peptide (atria) and brain natriuretic peptide (ventricles)
What substance is secreted into the lumen of the renal early proximal convoluted tubule (PCT) to provide a buffer for H+ ions and allow greater renal secretion of H+?
In the nephron, what happens to glucose in the proximal convoluted tubule (PCT)?
Glucose is fully reabsorbed in the PCT for blood glucose levels < 200 mg/dL (threshold)
What is vasopressin (ADH) secreted in response to?
Increased plasma osmolarity and reduced blood volume
What effect does vasopressin (ADH) exert on the number of aquaporins and H2O reabsorption in the nephron collecting tubules?
ADH binds to receptors on principal cells, resulting in a greater number of H2O channels (aquaporins) and increased reabsorption of H2O
On what segments of the nephron does parathyroid hormone exert its effects?
The proximal and distal convoluted tubules
What is angiotensin II secreted in response to?
A decrease in blood pressure
What are the 3 components of the glomerular filtration barrier?
Fenestrated capillary endothelium, basement membrane with type IV collagen, visceral epithelial layer
What is the formula for calculating the anion gap?
Anion gap = Na+ - (Cl- + HCO3-)
Name 3 triggers of renin release by the juxtaglomerular cells.
Decrease in renal blood pressure, reduced delivery of NaCl to the distal tubule, increase in sympathetic tone (β1)
What fluid compartment can inulin or mannitol measure?
What hormones influence blood volume and serum osmolarity via the renin-angiotensin-aldosterone system?
Antidiuretic hormone regulates osmolarity and blood volume; aldosterone regulates blood volume
What substances are largely reabsorbed in the early proximal convoluted tubule (PCT)?
All amino acids and glucose and most HCO3-, Na+, Cl-, K+, PO43-, H2O, and uric acid
What happens to the osmolarity of urine as it passes through the thick ascending loop of Henle?
Becomes increasingly hypotonic (diluted) because membrane is impermeable to water
How does paracrine secretion of prostaglandins affect renal blood flow (RBF)?
Causes dilation of afferent arterioles, leading to increased RBF
Angiotensin II (AT II) acts on the hypothalamus, resulting in what physiologic change?
What fluid compartment can radiolabeled albumin measure?
Other sets by this creator
CABS RENAL EM
Chem 111 Chapter 4&5 Test
Other Quizlet sets
6. Chordate diversity
Study Guide for 25 & 26
Sly giác quan
ECONO 2202 CH 2