Lecture 18 Flashcards
non electrolytes in Plasma that do not get filtered
- in mg/dL
280
150
125
100
15
10
3
1.5
0.5
trace
Phospholipids
Cholesterol
Fats
Glucose
Urea
Lactic acid
Uric acid
Creatinine
Bilirubin
Bile salts
positive and negative charges ______ intracellular fluid
positive and negative charges ______ in extracellular
equal
equal
______ is when Fluid has the same osmolarity as plasma
Things that can be given to patients
1. Normal Saline (__________)
2. _________________
Sodium, potassium, calcium (all as chlorides) and bicarbonate as a buffer.
Lactate may be used as a buffer (despite the fact that it is pH 6.5)
isotonic
N/S or 0.9% NaCl
Ringers Acetate(RA), Ringer’s lactate (RL)
_____ is when Fluid has fewer solutes (_____ mOsm/L) than plasma
Water, ___________
D5W (___________) after the sugar is used up
hypotonic
<282
1/2 N/S (0.45% NaCl)
5% dextrose in water
_______ is when Fluid has more solutes (_____ mOsm/L) than plasma
_______ in Normal Saline (_____)
___% saline solution, D5 in ___.
hypertonic
>282
5 % Dextrose (D5 N/S)
3%
RL
examples of isotonic solutions
Normal Saline (N/S or 0.9% NaCl)
Ringers Acetate(RA), Ringer’s lactate (RL)
examples of hypotonic solutions
Water, 1/2 N/S (0.45% NaCl)
D5W (5% dextrose in water) after the sugar is used up
examples of hypertonic solutions
5 % Dextrose in Normal Saline (D5 N/S)
3% saline solution, D5 in RL
sodium regulation occurs primarily in the _____
Majority is absorbed in the _________
Normally less than ____ % of filtered serum sodium is excreted
proximal nephron
1%
Most biologically active mineralocorticoid secreted by adrenal cortex
Aldosterone
aldosterone has
direct effect on sodium _______
Indirect effect on ___________
reabsorption
K+, Cl, Bicarb, pH
Overall kidney osmolarity
The cortex of the kidney (in Yellow) is very ____ in sodium
The outer medulla gets ______.
The inner medulla, which the loop of Henle dips into at its deepest, is ______
low
saltier
very salty
If Na+ and H20 reabsorbed equally – There will be_____ in Na+ concentration (and lacking other solute changes,
______ in osmolality or tonicity).
Allows rise in tubular _____ which facilitates the passive Na+ resorption distal proximal tubule
no change
no change
Cl-
Proximal Tubule
Reabsorbs iso-osmotically _____% filtered NaCl + H2O
Reabsorbs ____ % of the filtered HCO3-
Reabsorbs _____ of filtered glucose + amino acids
Reabsorbs K+, phosphate, calcium, magnesium, urea, uric acid
Secretes organic anions; urate, cations; creatine; protein-bound drugs, toxins
60 -65
90
almost all
loop of henle
Descending loop; begins at the end of the _____
____ ascending loop
_____ ascending loop-ends in the ________
Not uniform in appearance
doesn’t change tonicity*
pars recta
Thin
Thick
macula densa of the Distal Collecting Tubule.
loop of henle Plays a major role in the excretion of urine with high solute levels (_______ urine)
Reabsorbs _____ % filtered NaCl (normal intake of fluid and sodium)
______ multiplier as NaCl reabsorbed in excess of water
Major site of active regulation of ___ excretion
hyperosmotic
25 -35
Countercurrent
Mg
countercurrent mechanism
Contributes to the maintenance of the osmotic gradient in the renal medulla (Salty medulla)
The primary event: active ____ transported out of the________ of the loop of Henle into the _______
NaCl
thick ascending limb
medullary interstitium
Countercurrent Mechanism Permits the kidney to excrete urine with an osmolality that varies widely in humans
from a minimum of ___ mosmol/kg to a maximum of _____ mosmol/kg
50
900 to 1400
Descending limb, Loop of Henle
Urine delivered from the proximal tubule becomes _______ in the descending limb as it equilibrates with the medullary interstitium
Mechanism is water movement ____ of tubule, passively. (reabsorption)
hyperosmotic
OUT
Ascending limb, Loop of Henle
Filtrate then becomes _________ in the ascending limb as NaCl is _____ transported (reabsorbed) without water
The ascending limb is passively impermeable
The NaCl removed in the _____ is primarily responsible for the “salty” nature of the renal medulla
hypoosmotic (lower levels of fluid, NaCl being reabsorbed)
actively
ascending limb
Distal Collecting Tubule
Reabsorbs __________
5% filtered NaCl, no water
Distal Connecting Tubule and Cortical Collecting tubule
Late DCT and collecting duct are similar
(including some H2O reabsorption in Collecting duct)
Medullary Collecting Tubule
____________ of the urine
____________ NaCl
concentration can be reduced to less than ___ meq/L
Reabsorb ______ relative to the amount of antidiuretic hormone present,
allows a concentrated or dilute urine to be excreted**
Final modification
Reabsorb
1
H20 and urea
Final osmolality of the urine in the collecting tubules is dependent upon____:
ADH
ADH present collecting tubule:
water permeability is ______, allowing osmotic equilibration of the tubular fluid with the iso-osmotic interstitium in the cortex and then the hyperosmotic interstitium in the medulla.
Results in excretion of a ________ urine
ADH also contributes to the ____ medullary osmolality by permitting urea entry into the interstitium (helps to maintain osmolarity of medulla)
increased
concentrated
high
ADH absent:
________ urine leaving the loop of Henle does not __________, and a _____ urine is excreted
hypoosmotic
equilibrate with the interstitium
dilute
the composition an volume of the tubular fluid are essentially the same at the end of the loop of henle as the excretion of concentrated or dilute urine is determined primarily in the ________
collecting tubules
medullary collecting tubule also …
Secretes ________, (or retain)
urine pH can be reduced to as low as ______
Contributes to _______ balance by reabsorption or secretion
H+ and NH3
4.5 to 5.0
potassium
Composition of UrineDiffers from constant extracellular fluid in two ways:
Quantity of solutes and water in the urine is highly _______ as opposed to ECF
Ions compose ___ percent of the extracellular fluid solutes whereas urine has high concentrations of ______ (___). Urine offered an ____ for urea and other metabolic end products rather than accumulating in body
variable
95
uncharged molecules (urea)
exit
Quantity of solutes and water in the urine is highly variable as opposed to ECF
- Dependent on the intake of these substances
- In both instances, steady-state __________________
- Urine volume is greater after a water load than after water restriction
- Stable plasma Na+ concentration† (_____ mEq)
No absolute “_____” values for urinary solute or water excretion
Normal range reflects range of dietary intake, eg, 100 to 250 meq/day for Na+
(extracellular volume) - output = intake
145
normal
Obligatory Urine Volume (OUV)
_______________
- Avg 70 kg person = 600 mOm solute/day
Maximum concentrating ability 1200 mOm/L
OUV = ?
Minimum amount to rid waste
600/1200 = 0.5 L/day
Urine Specific Gravity
- Rapid estimate of urine solute concentration (weight)
- Range: ________
Affected by _________ such as glucose, contrast, ABX
more urine specific gravity = more _________
1.002-1.028
large molecules
urine osmolarity
Solute reabsorption drives water reabsorption via _____
___% of water reabsorption by the kidneys occurs along with solute ______ (such as Na+, Cl-, and glucose)
This type of water reabsorption is termed _______-because the water is “obliged” to follow the solutes
occurring mainly in the ______ of the loop of Henle
osmosis
90
reabsorption
obligatory water reabsorption
proximal tubule and desecending limb
Reabsorption of the final ____% of water occurs in the _____
This type of reabsorption is regulated by ___ and occurs in the _______
10
collecting ducts
ADH
collecting ducts
