Diuretics & Electrolytes Flashcards

1
Q

diuretic due to blockade of carbonic anhydrase, principal uses include urinary alkalinization, treatment of metabolic alkalosis, acute mountain sickness and glaucoma

A

acetazolamide

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2
Q

causes hyperkalemia until that excess plasma K+ is excreted, and then hypokalemia is a possibility

A

acidosis

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3
Q

when Fanconi syndrome is caused by multiple myeloma or nephrotic syndrome, for example, the condition is characterized as being ______

A

acquired

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4
Q

aka vasopressin, released by posterior pituitary, plasma levels of this are not normally affected by blood volume, but go up dramatically (e.g., higher than seen with osmolality changes) when effective plasma volume is more than 10% below its set point

A

ADH

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5
Q

5% solution could be infused to try to expand the plasma volume; low levels of this in plasma decrease total Ca2+ without decreasing ionized Ca2+ (so need to calculate this value)

A

albumin

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6
Q

adrenal hormone that promotes K+ excretion with Na+ retention; low levels during hypokalemia act to keep K+ from entering cells while high levels during hyperkalemia facilitate the exit of excess K+ from cells for renal elimination

A

aldosterone

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7
Q

administration corrects plasma K+ levels in type 1 RTA, can worsen them in type 2 RTA if it ends up in urine

A

alkali

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8
Q

a diuretic that blocks epithelial sodium channels (EnaC) in the principal cells of the collecting ducts

A

amiloride

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9
Q

potent vasoconstrictor and sodium retaining hormone due to direct effects in kidney, its selective efferent constriction helps maintain GFR as renal perfusion pressure falls, also stimulates aldosterone secretion

A

angiotensin II

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10
Q

electroneutrality principle states that there must be one of these for every cation in a compartment; the charge separated when combination of concentration difference and permeabilities means that one of the particles would prefer to be in another compartment is what gives rise to membrane and transepithelial potential differences (voltages)

A

anion

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11
Q

abbr., released from the heart by overfilling, acts in the kidney to increase GFR and decrease Na reabsorption (= increase Na excretion) to cause a decrease in effective plasma volume

A

ANP

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12
Q

substance that promotes free water clearance

A

aquaretic

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13
Q

occurs in liver disease due to impaired synthesis of plasma proteins and increased portal venous pressure

A

ascites

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14
Q

occurs in kidney at least in part by tubuloglomerular feedback and myogenic mechanism, means that GFR and RBF are approximately constant over a mean arterial pressure range of ~90 to 150 mm Hg

A

autoregulation

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15
Q

syndrome with effects similar to a loop diuretic… urinary loss of Na+, K+, Ca2+, Mg2+, hypochloremic metabolic alkalosis, inability to concentrate or dilute urine

A

Bartter

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16
Q

contains most of the Ca2+ and phosphate in the body and ~half of the Mg2+

A

bone

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17
Q

surprising consequence of hyperkalemia, occurs because hyperkalemia increases K+ conductance in SA nodal tissue enough to cause membrane hyperpolarization; other regions of heart do become hyperexcitable so arrhythmias likely

A

bradycardia

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18
Q

swelling of this organ by rapid onset hyponatremia or too-rapid correction of chronic hypernatremia can have catastrophic consequences

A

brain

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19
Q

a loop diuretic with similar adverse effects as furosemide but a more predictable oral absorption, doesn’t end in “semide”

A

bumetanide

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20
Q

expression is increased in DCT by calcitriol, needed for transcellular movement of large amounts of Ca2+ without causing apoptosis

A

calbindin

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21
Q

calcium regulatory hormone often ignored, it promotes excretion of both Ca2+ and PO4—

A

calcitonin

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22
Q

1,25 OH vitamin D3, the biologically active form that promotes intestinal absorption of Ca2+ and PO4— and the breakdown of bone to release Ca2+ and PO4—

A

calcitriol

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23
Q

administered IV to quickly antagonize cardiac effects of hyperkalemia (raises the action potential threshold)

A

calcium

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24
Q

a cause of real hyperkalemia and pseudohyperkalemia (2 words)

A

cell lysis

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25
refers to form of diabetes insipidus when damage to the hypothalamus or posterior pituitary gland disrupts ADH release
central
26
similar to hydrochlorothiazide but longer half-life, favored by some hypertension specialists in part because it is the only thiazide with proven cardiovascular benefits; doesn't end in "thiazide"
chlorthalidone
27
characterizes 1:40,000 incidence of Gitelman syndrome relative to that of Bartter and especially Liddle syndrome
common
28
ability impaired in the kidney by loop diuretics, Bartter syndrome and hypokalemia (here presumably due to need for K+ by Na+-K+-2Cl- cotransporter) resulting in polyuria and nocturia (2 words)
concentrating
29
prototype for the non-peptide V2 receptor antagonists that can be used judiciously to treat euvolemic and hypervolemic hyponatremia unresponsive to fluid restriction; causes water excretion without solute excretion
conivaptan
30
common abbr., infused when the ultimate objective is to add water to the body without solute
d5w
31
osmotic _____ syndrome (formerly called central pontine myelinolysis) is ~irreversible consequence of correcting hyponatremia too rapidly (among its manifestations is the "locked-in" syndrome where patients are awake but unable to move or communicate, except perhaps by blinking)
demyelination
32
cause of hypokalemia; inability of glucose to enter cells keeps K+ in plasma and loss of glucose in urine then creates polyuria/volume contraction which stimulates aldo release and that plasma K+ is therefore also excreted in the urine (2 words)
diabetes mellitus
33
an extrarenal cause of hypovolemia and often hypokalemia (and hypomagnesemia) with metabolic acidosis; it can be induced by magnesium ingestion
diarrhea
34
substance that promotes excretion of urine
diuretic
35
whether extracellular or intracellular, means that too much sodium is in this compartment (water followed); common indication for a loop diuretic
edema
36
having tone fall in this arteriole decreases glomerular hydrostatic pressure; GFR falls but remaining kidney function is better preserved (e.g., in diabetes)
efferent
37
its effects on cells with beta2 receptors on skeletal muscle causes K+ uptake while binding to alpha receptors on hepatocytes promotes K+ efflux
epinephrine
38
aldosterone antagonist with greater selectivity than spironolactone
eplerenone
39
loop diuretic that can be used by patients with sulfa allergy
ethacrynic acid
40
causes a rise in extracellular K+; happens because Na+ influx with K+ efflux occurred during cell activation +/- depletion of ATP reserves needed for its restoration to baseline
exercise
41
hypovolemic hyponatremia with low sodium in the urine suggests Na+ was lost due to vomiting, diarrhea, third spacing of fluids, etc., collectively referred to as this type of Na loss
extrarenal
42
syndrome typically considered a general defect in the function of proximal tubule where solutes that are normal reabsorbed such as glucose, amino acids, phosphate, uric acid and bicarbonate are passed into the urine
Fanconi
43
released by bone, it acts in kidney to promote PO4--- excretion; a major regulator of PO4--- excretion with familial abnormalities and instances of ectopic secretion
FGF-23
44
type of paralysis associated with hyperkalemia; somatic nerves fired/released Ach once but cannot repolarize to fire again (i.e., resting membrane potential is above threshold potential)
flaccid
45
with a sodium load, an increase in this in the distal tubule increases K+ secretion while the associated decrease in aldosterone decreases K+ secretion, together allowing for elimination of excess sodium without K+ loss or retention (2 words)
flowrate
46
this clearance is zero when urine is isotonic, positive when urine is dilute and negative when urine is hypertonic; negative means that the water in which urinary solute was diluted has been returned to the body to dilute to lower plasma osmolality
free-water
47
can be administered along with saline to treat hypercalcemia
furosemide
48
when low, Na+, K+, H+, Mg2 +, PO4--- and urea are among the solutes kidneys struggle to eliminate
GFR
49
syndrome with effects similar to a thiazide diuretic typically manifesting in late childhood/early adolescence characterized by urinary loss of Na+ and K+ with hypochloremic metabolic alkalosis, < normal urinary loss of Ca2+ but much loss of Mg2+ leading to severe hypomagnesemia (a reflection of reabsorption differences for Mg2+ and Ca2+ in the proximal tubule)
Gitelman
50
balance that represents a combination of physical forces intrinsic to the kidney that helps keep proximal tubular reabsorption proportional to GFR
glomerulotubular
51
potential adverse effect of spironolactone use by males
gynecomastia
52
chemical abbr, examples where it can be lost in excess of Na+ to cause hypernatremia include exhaled air, sweat and when paired with glucose in urine
H2O
53
abbr, plasma levels of this can be < 10 mEq/L in type 1 RTA, range from 12 -20 mEq/L in type 2 RTA depending upon degree of distal compensation, and are typically > 17 in type 4 RTA
HCO3
54
___ metals, refers to elemts such as cadmium, lead and mercury that damage the proximal tubule to cause Fanconi syndrome
heavy
55
chicory, dandelion leaves, fennel, goldenseal and many others are diuretics of this type of alternative medicine with generally uncharacterized mechanisms of action and uncertain efficacy
herbal
56
potential adverse effect of spironolactone use by females
hirsutism
57
ion that exchanges with cellular K+ during acid-base maintenance and/or compensation; reason acidosis can cause hyperkalemia
hydrogen
58
pressure that exists across the capillaries that is not present across cell membranes, drives filtration in glomerulus, increased in capillaries by plasma volume overload, heart failure, venous obstruction/valve dysfunction and arteriolar vasodilatation
hydrostatic
59
a good guess if patient is hypertensive, hypervolemic, hypernatremic and hypokalemic with metabolic alkalosis; converse suggests hypo___
hyperaldosteronism
60
primary hyperparathyroidism, cell destruction associated with malignancy, excessive intake of antacids and thiazide diuretics are among its common causes
hypercalcemia
61
characteristic of the metabolic acidosis seen with K+-sparing diuretics
hyperchloremic
62
a common cause of hyponatremia despite a high plasma osmolality (i.e., means there is an abundant plasma solute other than Na); thiazide and loop diuretics are drug-induced causes of this likely secondary to their K+-losing properties
hyperglycemia
63
means plasma K+ conc is > 5.2, decreases resting membrane potential of most cell membranes, tall peaked T wave on ECG is among signs; caused by ACEI/ARB or aldo antagonists
hyperkalemia
64
when severe, a cause of isotonic hyponatremia (aka pseudohyponatremia, due to presence of volume in which Na+ is not dissolved)
hyperlipidemia
65
means plasma levels are >2.2 mg/dL, rare unless massive intake of Epsom salt or kidney failure; often asymptomatic but can eliminate with loop or thiazide diuretics or dialysis
hypermagnesemia
66
means plasma Na+ concentration is > 145 mEq/L, seen in ~1% of hospitalized patients; associated with high morbidity and mortality, especially in elderly
hypernatremia
67
a consequence of the inability to eliminate its dietary intake during chronic kidney disease, causes deposition of Ca2+ in soft tissues and a fall in ionized Ca2+ levels in plasma
hyperphosphatemia
68
common reason for administering a thiazide diuretic
hypertension
69
3% saline for example, it expands the ECF volume in large part by extracting intracellular water; useful for treating hyponatremia with severe symptoms
hypertonic
70
caused by loop and thiazide diuretics, increase the risk of gout
hyperuricemia
71
evidence for this includes weight gain, edema and a bounding pulse
hypervolemia
72
type of hyponatremia that occurs when what is sensed as a decrease in effective arterial volume due to, for example, congestive heart failure, liver disease and nephrotic syndrome leads to ADH secretion; both water and sodium are retained with a relative excess of water
hypervolemic
73
paresthesias, tingling, weakness, cramping, irritability, dysrhythmias and Chvostek and Trousseau signs are among the clinical features
hypocalcemia
74
type of metabolic alkalosis seen with thiazide and loop diuretics secondary to K+ loss
hypochloremic
75
means plasma K+ conc is < 3.7, hyperpolarizes most cell membranes, shallow T wave with U wave on ECG is among signs; is it caused by K+- losing diuretics (also remember this increases digoxin toxicity)
hypokalemia
76
means plasma level is < 1.7 mg/dL, often coexists with hypokalemia and hypocalcemia; contributes to clinical signs such as muscle weakness, tremors, tetany, seizures, paresthesias, vertical and horizontal nystagmus, torsades de pointes
hypomagnesemia
77
means plasma Na+ concentration is <135 mEq/L; seen in 15-20% of hospitalized patients, it is the most common electrolyte abnormality seen in clinical practice
hyponatremia
78
calcium and vitamin D supplements are treatment for hypocalcemia due to this
hypoparathyroidism
79
refers to, for example, 0.45% NaCl which when infused expands the ECF and to a lesser extent the ICF volume as osmotic differences across cell membranes equalize
hypotonic
80
seeing skin tenting, dry mucous membranes, sunken eyes and evidence of oliguria during a bedside exam is evidence of this
hypovolemia
81
hyponatremia when excessive sodium loss in the urine due to diuretics or mineralocorticoid deficiency has lowered effective circulating volume enough that ADH secretion has been triggered in a compensatory effort
hypovolemic
82
causes of this type of Fanconi syndrome include cystinosis, galactosemia and Wilson disease
inherited
83
form of diabetes that is a potentially surprising cause of euvolemic hypernatremia; stretch receptors only monitor/maintain effective circulating volume irrespective of its osmolality
insipidus
84
allows glucose to enter cell, phosphate and potassium follow; it plus glucose is treatment for hyperkalemia
insulin
85
type of edema associated with tissue ischemia
intracellular
86
refers to 0.9% NaCl which selectively expands extracellular fluid volume, e.g., in shock; also used to treat hypovolemic hypernatremia since both Na and water are needed
isotonic
87
failure of these can cause hypervolemic hyponatremia with an increased effective arterial volume; also don't get OH added to 1 position of 25 hydroxyvitamin D3 and major pathway for PO4--- elimination is lost
kidneys
88
broad characterization of diuretics that includes thiazides, loop diuretics, carbonic anhydrase inhibitors and osmotic diuretics
K-losing
89
class of diuretics acting in the collecting duct to block Na+/K+ exchange, useful to counterbalance an adverse effect of loop and thiazide diuretics
K-sparing
90
Gitelman syndrome has some predilection for the female gender and tends to be more benign than Bartter syndrome, with typical symptom onset in _____ childhood
late
91
"real" European form of this contains glycyrrhizic acid as its sweet tasting ingredient, which alters steroid metabolism in a manner that exaggerates mineralocorticoid effects; thus, ingestion of real licorice can cause symptoms of hyperaldosteronism
licorice
92
extremely rare syndrome with early/severe hypertension, hypokalemia with low plasma renin activity and low to normal aldo levels; caused by failure of EnaC channels to degrade properly once synthesized; treated with low Na+ diet and K+-sparing diuretics
liddle
93
organ that synthesizes albumin, coagulation and complement factors, and adds OH to 25 position of vitamin D3
liver
94
diuretic class that is a secondary choice for hypertension unless GFR is low (e.g., GFR < 30 ml/min) since it will still work then while thiazides become ineffective
loop
95
blockade of its drainage by, for example, cancer, various infections, or surgery, can cause edema
lymph
96
ionized form of this divalent cation is a crucial cofactor in many biological processes, plasma levels are maintained in normal range by regulation of reabsorption through TRPM6 channels in DCT in a still poorly understood manner; both loop and thiazide diuretics cause it to be lost in urine
magnesium
97
can cause a severe hypercalcemia, bisphosphonate drugs used to treat osteoporosis are sometimes administered to precipitate the Ca2+ to decrease the ionized Ca2+ levels
malignancy
98
example of an osmotic diuretic administered in gram quantities to help eliminate excess intracellular volume (e.g., causing elevated intracranial pressure), now often supplanted by hypertonic saline
mannitol
99
aka "ecstasy", coupling this ADH release stimulating drug with admonishments to drink at rave dance parties can cause life threatening hyponatremia
MDMA
100
form of alkalosis that occurs when K+ (and Cl-) are lost in urine due to diuretics or hyperaldosteronism, and cells donate K+ while taking up H+ (and leaving behind HCO3-) in an effort to maintain hypokalemic plasma K+ levels closer to normal (2 words)
metabolic
101
long-acting thiazide diuretic favored by cardiologists as adjunct in treatment of congestive heart failure, doesn't end in "thiazide"
metolazone
102
co-transporter in the DCT that acts to further dilute the tubular fluid; target of thiazide diuretics
nacl
103
common name for transporter in TAL that, in combination with water impermeability and direction of flow outside of TAL, gives rise to dilute tubular fluid and a hypertonic renal medullary interstitium; target of loop diuretics
nak2cl
104
transporter in proximal tubule regulated to control plasma PO4--- levels (e.g., by PTH and FGF-23)
napi2
105
substance that promotes renal excretion of sodium
natriuretic
106
abbr. for the sympathetic neurotransmitter; a vasoconstrictor, it constricts afferent arteriole to decrease GFR and promotes Na+ reabsorption by tubules to promote an increase in effective plasma volume
NE
107
hypernatremia in nursing home residents is a known indicator of this
neglect
108
refers to form of diabetes insipidus when kidney fails to respond to ADH (treatment is HCTZ if congenital, amiloride if due to Li+ toxicity from bipolar therapy)
nephrogenic
109
syndrome in which there is generalized infiltration of edema into the subcutaneous connective tissue (anasarca) because albumin/other proteins are lost in the urine faster than they can be replaced
nephrotic
110
outdated tetracycline, cisplatin, aminoglycosides and tenofovir are among the proximal tubule _____ that cause the Fanconi syndrome
nephrotoxins
111
character of the most prominent manifestations of hypokalemia (includes life-threatening weakness of diaphragm)
neuromuscular
112
along with the need for lifelong increases in dietary Na+ and K+ intake and use of K+-sparing diuretics, patients with Bartter syndrome but not Gitelman syndrome will benefit when blockade of PGE2 production with these limits counterproductive renin secretion
NSAIDS
113
the "suck" pressure in the vasculature due to proteins trapped in blood vessels; opposes filtration in glomerulus, drives reabsorption in peritubular capillaries; loss causes edema
oncotic
114
a small decrease in this for plasma drives a large decrease in this in urine because ADH secretion is turned off (= solute particles/kg of water)
osmolality
115
located in the hypothalamus, they sense the concentration of solutes in the plasma and act on neurons in the supraoptic and paraventricular nuclei to bring this value back to the desired level
osmoreceptors
116
renal ____ refers to bone demineralization due to high PTH levels seen in chronic kidney disease
osteodystrophy
117
well known toxicity of loop diuretics
ototoxicity
118
major pathway for Mg2+ reabsorption in TAL, Ca2+ is also reabsorbed here in addition to its reabsorption in proximal tubules
paracellular
119
the movement of immunoglobulins, coagulation factors, complement factors, and of course albumin into the extracellular space after a mosquito bite is because this increased for proteins in the capillary/venular endothelium
permeability
120
abundant in the typical diet with ~900 mg needing renal elimination each day; very problematic when GFR falls and must reduce intake (10) 70 means plasma Na+ concentration is
phosphorus
121
primary form can cause hyponatremia but not hypervolemia
polydipsia
122
predominant intracellular cation, rapid distribution into tissues after a meal plus urinary elimination is crucial for maintenance of extracellular K+ in the normal range after a meal; plasma levels of this are usually low in type 1 and type 2 RTA, always high in type 4 RTA
potassium
123
refers to euvolemic hyponatremia due to excessive consumption of beer (i.e., occurs because beer has calories but few electrolytes)
potomania
124
inhibitors of this in stomach are well known for their ability to suppress Mg2+ absorption from GI tract to potentially cause hypomagnesemia; some now question clinical importance of this
proton pump
125
tubule where there is a significant amount of Ca2+ reabsorption but very little Mg2+ reabsorption
proximal
126
hormone with secretion rate governed by Ca2+ sensing receptors that act to maintain the level of ionized Ca2+ in the plasma
PTH
127
________ hypophosphatemia refers to a potentially life-threatening situation triggered by providing food to the starving or force-feeding an anorexic person
refeeding
128
form of acidosis that means there is acidemia with a normal anion gap, normal serum creatinine and no diarrhea (3 words)
renal tubular
129
___-age, refers to when symptoms of a child with Bartter syndrome are typically first noticed, perhaps in association with vomiting and growth retardation
school
130
form of hypoparathyroidism seek in CKD, occurs due to inability of kidney to synthesize calcitriol needed for Ca2+ absorption from diet (so hypocalcemia) and inability to excrete phosphate (so hyperphosphatemia)
secondary
131
causes euvolemic hyponatremia rather than hypervolemic hypovolemia because the regulators of effective plasma volume cause the sodium in the excess volume to be lost (abbr)
SIADH
132
characterizes the on and off-rate for drugs such as spironolactone that affect protein expression
slow
133
aka oat, describes the cells of lung carcinoma that is a classic cause of ectopic ADH production
small
134
cation that ~only gets into a cell if it drives a desired objective, e.g., reabsorption of items filtered into proximal tubule that typically need to undergo net reabsorption for maintenance of body homeostasis (e.g., glucose, bicarbonate, phosphate, amino acids)
sodium
135
classical aldosterone antagonist, its effects in the principal cells of the collecting duct cause it to act as a K+-sparing diuretic
spironolactone
136
likelihood of formation from calcium in the urinary pelvis is increased by loop diuretics and decreased by thiazide diuretics due to their differing effects on its reabsorption
stones
137
receptors that measure effective vascular volume as an index of body sodium content; they alter activities of the renin-angiotensin aldosterone system, sympathetic nervous system, and atrial natriuretic peptide release
stretch
138
allergy that causes some people to be unable to tolerate many of the loop and thiazide classes of diuretics; their molecular structure contains a specific element
sulfa
139
this acting on the skin promotes formation of vitamin D3 from cholesterol, vitamin D is also obtained from diet
sunlight
140
hypercalcemia raises this "potential" meaning excitable tissues are less likely to fire; predictable symptoms include constipation, muscle weakness, confusion
threshold
141
selective non-peptide V2 receptor antagonist that can be administered orally to patients with hyponatermia despite water restriction; use > 30 days increases risk of hepatotoxicity
tolvaptan
142
blocks EnaC channels in the principal cells of the connecting tubule and collecting duct, similar to amiloride
triamterene
143
channel responsible for Ca2+ reabsorption in DCT, major site of regulation with calcitriol increasing its synthesis and PTH helping to regulate its conductance
TRPV5
144
classic form of RTA in which there is impaired distal H+ secretion, typically caused by autoimmune disorders, kidney transplantation, other conditions where there is damage/fibrosis in collecting duct regions
type 1
145
means there is RTA due to impaired reabsorption of HCO3- by proximal tubule
type 2
146
most common form of RTA, occurs due to lack of aldosterone or renal response to it? --> diminution of H+ secretion in distal nephron +/- impairment of ammoniagenesis in proximal tubule needed for buffering secreted H+ during bicarbonate regeneration in distal nephron
type 4
147
this for both sodium and water increases as MAP increases; alterations in Na+ regulating factors shift the relationship along the x (i.e., MAP) axis; intersection of this relationship with that for average daily Na intake is theoretical set point for arterial blood pressure regulation (2 words)
urinary output
148
typically > 5.5 in type 1 RTA due to impaired distal H+ secretion, < 5.5 in type 2 and type 4 RTA (word + abbr)
urine pH
149
hypernatremia and hyponatremia are a problem with the body's regulation of this
water