April 7th- April 11th Renal

Question 1

70. Compare the pattern of water reabsorption and tubular filtrate osmolality in maximum antidiuretic and maximum diuretic states; also compare the final urine flow and osmolality.

Answer 1

In the presence of high ADH, much water is absorbed in the collecting ducts and increased amount of urea is absorbed in the collecting ducts; osmolality is increased at the bottom of the loop of Henle and the bottom of the collecting ducts and flow is drastically reduced. In the absence of ADH osmolarity does not increase nearly as much in the bend of the loop of Henle and in the collecting duct and flow is maintained at higher levels through these places

Question 2

71. Describe the pathology underlying the condition diabetes insipidus, and explain what clinical test can be performed to determine whether the defect resides at the level of the pituitary or kidney. How can diabetes insipidus be differentiated from psychogenic polydipsia?

Answer 2

Insensitivity to (kidney) or lack of production (pituitary problem) of ADH leads to production of high volumes of urine that is dilute, people with diabetes should have a high level of ADH and continues well into a state of dehydration (unlike psychogenic polydipsia)

Question 3

How does ADH change the filtrate flow?

Answer 3

ADH will decrease flow more in the cortical collecting duct and will take flow down to its minimun in the medullary collecting duct

Question 4

What is the effect of ADH on filtrate osmolality?

Answer 4

ADH increases the osmolality of filtrate significantly in the loop of Henle and the medullary collecting duct

Question 5

72. List the three common goals of the kidneys and cardiovascular system in their regulation of the sodium and water balance of the blood.

Answer 5

homeostatic blood voluem and pressure, homeostatic blood and cell osmolality and kideny blood flow and functions

Question 6

73. List two general ways that the kidneys influence the volume of blood.

Answer 6

maintain water balance as well as blood cell production

Question 7

74. Outline the logic (using equations where possible) that explains why the bodyÕs sodium content is a crucial determinant of the ECF and blood volumes.

Answer 7

in ECF volume control, sodium is the key; osmolality directly influecnes the movment of water and therefore ECF and blood volumes (in the face of tightly controled ECF osmolaltiy, ECF volume varies directly with the sodium content)

Question 8

75. Explain how whole-body sodium content is detected/monitored.

Answer 8

Detection of sodium content is indirect, based mainly on vascular pressures, assessed by cardiovascular baroreceptors

Question 9

76. List the three categories of baroreceptors and describe, in general, their regulatory targets.

Answer 9

Arterial baroreceptors (mediate classic baroreceptor reflex) and cardiopulmonary baroreceptors work in parallel in response to changes in atrial pressure to affect TPR, cardiac performance, sympathetic drive to kidney and venous compliance through the branstem vasomotor center and the hypothalamus; the third type is intrarenal baroreceptors which independently regulate renal blood pressure

Question 10

How do intrarenal baroreceptors work?

Answer 10

JGA afferent arteriole cells act on sustained deviations in blood pressure by changing renin secretion

Question 11

77. State the location/identity of the intrarenal baroreceptors, and list the two ways they receive information about blood pressure.

Answer 11

Intrarenal baroreceptors sense renal afferent arterial pressure by specializations of the afferent arteriole: granular cells (juxtaglomerular cells) that form part of the juxtaglomerular apparatus, stretching leads to an increase in renin production

Question 12

78. List the three mechanisms leading to secretion of the enzyme renin by the kidney.

Answer 12

two primary regulators of renin secretion are: neural baroreceptors which influence the activity of renal sympathetic nerves that stimulate granular cell production of renin AND intrarenal baroreceptros (granule cells) respond to adrenergic stimulation deform in response to changes in afferent arteriolar pressure by releasing more angiotensin with higher pressures. a third detector of mechanism that regulates renin release is macula densa that monitors the amount of tubular sodium chloride directly bathing the macula densa cells (high tubular sodium loads inhibit renin production

Question 13

79. Describe in detail the global renin-angiotensin system mechanism, including all stimulators of the system, component enzymes and intermediates, targets, and systemic effects.

Answer 13

Renin acts upon angiotensionogen to produce angiotensin I, which acted on by ACE to produce angiotensin II. (angiotensinogen is produced in the liver and ACE is expressed on the luminal surface of endothelial cells in many parts of the vasculature); targets: angiotensin II binds to cell surface receptors, it initiates actions that affect blood pressure and excretion of sodium; limiting reactant is the rennin that is available in blood to turn angiotensinogen to angiotensin I

Question 14

80. Explain how a kidney that has been transplanted into a patient (and which therefore has no neural inputs) is still able to participate in blood pressure control

Answer 14

JG cells that sense osmolality sense pressure independently of neural control and these set points are transplanted with kidneys

Question 15

81. Explain how regulation of GFR can play a role in regulating sodium balance.

Answer 15

when blood pressure is elevated, decreased sympathetic constriction of afferent arteriorles increases the filtered load of Na, favoring excretion

Question 16

Altough altering GFR can influence Na+ excretion, the main way of regulating ECF voluem is by changing what?

Answer 16

changing fractional reabsorption in the distal nephron

Question 17

82. Draw a diagram showing the neural and hormonal compensatory mechanisms that compensate for low effective circulating volume, including the sensors, mediators and effectors.

Answer 17

?

Question 18

83. List three mechanisms by which angiotensin II influences the rate of Na+ excretion by the kidney.

Answer 18

reduces the filtered load of Na via ateriole contstriction and decreased GFR, increases Na/H to directly reduce Na and water reabsorption in proximal tubule, simtulates aldosterone secretion and inhibits renin secretion (by negative feedback)

Question 19

84. Describe the phenomenon of pressure natriuresis, including its triggers, its mechanisms, and the overall function it serves in Na+ balance and control of the ECF volume

Answer 19

increased arterial and renal medulla pressure results in the release of aracidonic acid with inhibits Na/H antiproter and H2O reabsoprtion the proximal tuble and increase the excretion of Na an water, reducing the ECF and blood volume (couples Na+ and water excretion together)

Question 20

What is the difference between natriuresis and diuresis?

Answer 20

naturesis deals with loss of salt, diuresis has to do with loss of water

Question 21

85. List the main cellular targets of aldosterone in the nephron tubules, and explain the mechanism of its actions in those locations.

Answer 21

aldosterone acts in cortical collecting ducts to reabsorb Na+

Question 22

86. Quantify the percentage of the filtered Na+ that is regulated by the presence or absence of aldosterone, and convert that percentage into the actual numbers of mmol of NaCl/day and the number of grams of NaCl/day.

Answer 22

The percentage of sodium reabsorption dependent on the influence of aldosterone is approximately 2% which could lead to a significantly large quantity of sodium filtered, 12 g of Na+ or 30g of NaCl

Question 23

87. List areas of the body other than the kidney that are stimulated by aldosterone to reabsorb Na+.

Answer 23

aldosterone stimulates sodium transport also in sweat and salivary glands, serving as a an all-purpose salt retention system

Question 24

88. List two factors that stimulate aldosterone secretion, and one factor that inhibits it

Answer 24

Atrial natriuretic factors inhibit aldosterone secretion, angiotension II is the main stimulator of aldosterone, along with others like elevated plasma potassium concentrations

Question 25

89. Describe the general purpose of the autoregulation mechanisms, and they contribute (or don’t contribute) to returning Na+ levels toward homeostatic levels.

Answer 25

myogenic (smooth muscle response) and tubuloglomerular feedback (macula dense senses increased Na+ load and releases adenosine) cause vasoconstriction in the afferent arterioles which limit GFR, serving the purpose of reducing damage to glomerular capillaries but also reducing GFR and ability to filtrate water or sodium or both

Question 26

90. Give a general explanation (not involving the details of the transporters, paracrine messengers and receptors) for how and why the macula densa senses tubular flow and how that information feeds back to affect GFR and RBF.

Answer 26

decrease in plasma volume leads to increased activity of renal sympathetic nerves, decrease in arterial pressure, and a decrease in GFR, which causes decreased flow to macula densa; all of these cause an increase in renin secretion
(macula densa also senses increased Na+ load and releases ATP/adenosine which vasoconstricts afferent arterioles)

Question 27

91. Detail the mechanisms of the natriuretic peptides, including the stimulus for their secretion, the organ they are secreted from, their main targets, their effects on their targets, and their overall effect on blood pressure.

Answer 27

Natriuretic peptides promote excretion of sodium in the urine; main source is the heart and ANF has both vascular and tubular actions, primarily relaxing the afferent arteriole and therefore promoting increased filtration; major stimulus for increased secretion is distention of the atria; ANP release also decreases renin and aldosterone secretion

Question 28

92. Distinguish between the mechanisms of regulating Na+ that alter reabsorption of Na+ and water, from those mechanisms that alter reabsorption of Na+ only.

Answer 28

Sodium excretion works through two general types of mechanisms: (1) GFR and proximal tubule mechanisms that lead to coupled changes in sodium and water excretion or (2) distal nephron effects in which sodium can be reabsorbed independently of water NOTE: Proximal mechanisms are primarily involved in excreting excess ECF volume, whereas the distal mechanism alter sodium excretion when ingestion of sodium is not balance by ingestion of water

Question 29

93. State the two names for the hormone that allows the regulation of water excretion independent from solute excretion, and list the principal regions and cell types of the nephron where that hormone acts.

Answer 29

Antidiuretic hormone- arginine vasopressin: produced by the hypothalamus and collecting ducts are very sensitive to the action of ADH

Question 30

94. Describe the secretion mechanism and list the two major inputs that regulate the rate of secretion of the hormone ADH.

Answer 30

Secretion mechanism: H2O balance disturbed, blood fluid osmolarity changes, firing by hypothalamic osmoreceptors changes, ADH is release from the posterior pituitary into the blood, collecting ducts change their permeability to water, excretion or retention of water (input to the ADH secreting neurons include osmoreceptors— primary mechanism and cardiovascular baroreceptors– secondary mechanism)

Question 31

Match the following words together based on which mechanism the body modulates to control another: water balance, salt balance, osmolality, blood pressure

Answer 31

water balance (controlled by ADH and water excretion) controls osmolality;

salt balance (through rennin and aldosterone system) regulate blood pressure

Question 32

The factor that regulates water independently of Na+ is ____, which can be considered mainly a regulator of the ECF osmolality and thus _____ volume

Answer 32

ADH indirectly regulates ICF volume by controlling ECF osmolality

Question 33

95. Compare the urine osmolality and flow rate when the hormone cited in the previous two questions is present in high concentrations and low concentrations, explain how these differences are achieved, and explain the differential effect on the plasma osmolality.

Answer 33

In the presence of ADH, osmolarity should be increased and flow decreased within the length of the collecting duct, the difference is achieved by selectively reabsorbing water without effecting Na+ content of filtrate

Question 34

Is ADH secretion particularly useful in the case of hemorrhage?

Answer 34

it will reduce further H2O loss but it can not maintain balance with Na+ levels (at high levels ADH functions as a vasoconstrictor, helping increase mean arterial pressure but reducing GFR)

Question 35

96. Describe how the blood pressure influences, and is influenced by ADH.

Answer 35

increases in blood pressure decrease ADH, decreases in blood pressure increase ADH

Question 36

97. Explain how small and large changes in osmolality and blood pressure are prioritized in terms of the secretion of the above hormone.

Answer 36

In general the high sensitivity of the osmoreceptors influence predominates over that of the baroreceptors BUT when changes in osmolality and plasma volume are small to moderate although large reductions in plasma volume take precedence over decreased body fluid osmolality (which would stop ADH secretion)

Question 37

98. Explain how alcohol consumption affects your ability to homeostatically regulate water balance.

Answer 37

ethanol inhibits ADH release (causes you to loose lots of liquid, salty snacks will slow down this dehydration)

Question 38

99. Draw a diagram showing the physiological compensation mechanisms that help maintain homeostasis after severe sweating.

Answer 38

P461 loss of hypo osmotic salt solution results in a combination of decrease ECF volume and increased plasma osmolality activates reflexes that preserve both salt and water by increasing aldosterone and ADH respectively

Question 39

100. List the inputs to brain centers where the perception of thirst arises.

Answer 39

Centers that mediate thirst are located in the hypothalamus stimulated by both reduced plasma volume and increased body fluid osmolality- thirst response is less sensitive than the ADH response in humans

Question 40

101. Differentiate between hedonistic and regulatory salt appetite, and compare humans to other animals with regard to the relative importance of these two categories of appetite.

Answer 40

Hedonistic aptetite- animals like salt and eat it whenever they can regardless of whether are salt deficient and regulatory appetite- animals drive to obtain salt is markedly increased in the presence of deficiency; humans have a large hedonistic appetite for salt and salt cravings tend to minimal for everyday homeostasis

Question 41

102. Describe the sequelae of a renal artery stenosis, including what happens to blood pressure, levels of renin, angiotensin 2 and aldosterone. Also explain why treatment with an ACE inhibitor could result in elevated plasma urea and creatinine levels.

Answer 41

In renal artery stenosis the intrarenal regulators would experience low blood pressures which would initiate the renin- angiotensin II and aldosterone pathway, elevating all of those molecules, the body would see increasing blood pressure as a result of these changes and release increasing amounts of ANF, ACE inhibitors could decrease the GFR so that the creatinine and urea levels would be elevated

Question 42

103. Differentiate between the body compartment where the most total K+ exists, and the compartment which the concentration of K+ is most tightly regulated

Answer 42

Vast majority of K+ is in intracellular compartments, the 2% of total ECF potassium is tightly regulated because of its importance in nerve and muscle excitability

Question 43

104. Describe the mechanism that maintains high ICF K+ concentration.

Answer 43

large ICF pools buffer ECF changes via action of the Na/K ATPase (insulin stimulates the pump and epinephrine (trauma or exercise) stimulates the pump

Question 44

105. Explain why a high K+ meal does not cause a spike in the ECF K+ concentration.

Answer 44

Insulin released after a meal increases the action of Na/K ATPase; dietary loads are taken up into the intracellular compartment rapidly, the tissue that contributes most to sequestration of K+ is skeletal muscle because it contains the largest collective intracellular volume

Question 45

106. Describe the mechanism that helps prevent a rise in ECF K+ after intense exercise, or trauma.

Answer 45

The effect of epinephrine on cellular potassium uptake us probably of greatest physiological importance during exercise when potassium moves out of muscle cells that are rapidly firing AP, similar to trauma causing loss of K+ from cells, in both causes release of epinephrine causes reuptake of K+ into cells

Question 46

107. Describe the relationship between ECF pH and K+ concentration.

Answer 46

An increase in ion concentration is often associated with net potassium movement out of cells (H+ moves into cells to buffer acidity and do so in exchange for K+), whereas a decrease in ECF hydrogen ion concentration causes net potassium movement into them (mechanism is unclear)

Question 47

Describe the mechanism and the amount of K+ handled in the PCT.

Answer 47

movement in the PCT of K+ depends on Na+ and H2O absorption, 65% of K+ moves through paracellular routes in this section of tubule

Question 48

Describe the mechanism and the amount of K+ handled in the thick ascending loop of Henle.

Answer 48

K+ is transported across the apical membrane via NCCK transporters and then leave the basolateral membrane by K+ channels or K+/Cl- cotransporters, 25% of the K+ is absorbed from this section of tubule

Question 49

How much K+ is left in the DCT filtrate and what happens to the filtrate K+ content thereafter?

Answer 49

if the diet is K+ deficient, the remainder (10%) of K+ can be reabsorbed in distal tubule and collecting duct

Question 50

What hormone regulates the MAJORITY of K+ reabsorption?

Answer 50

there is little regulation of K+ reabsorption in any segment- there is no hormone that regulates reabsorption directly, reabsorption rate is affected chiefly by osmotic diuresis or clinical diuretics that act on proximal tubule Na+ reabsorption or loop diuretics (causes K+ depletion)

Question 51

109. List six factors that influence K+ secretion in the distal nephron, explaining how each alters K+ secretion.

Answer 51

K+ can be excreted by 1) transport of K+ into the tubule cell via the Na/K pump and then through channels in the apical membrane. (Na/K ATPase and Na, K+ channels are controlled by aldosterone) this mechanism regulated by aldosterone can secrete more K+ into the filtrate than was originally filtered

Question 52

What stimulates the principle cell K+ secretion?

Answer 52

high plasma potassium will increase aldosterone secretion, high Na delivery to the distal nephron will cause Na/K ATPase to increase, high flow rate in the distal nephron is sensed by kinocillium increases potassium secretion and also washes away ions that exit the K+ channel, high potassium diet causes activation of feed forward mechanism in the gut and non chloride anions in the distal nephron decrease the K+ gradient

Question 53

110. Distinguish between the action of diuretics that cause loss of K+ from the body vs those that are K+-sparing diuretics.

Answer 53

potassium wasting diuretics reduce the Na+ reabsorption prior to the principal cells which causes concurrent K+ dumping due to the action of Na/K ATPase, potassium sparing diuretics block Na channels in principal cells or block aldosterone receptors

Question 54

What does paradoxical K+ retention mean?

Answer 54

acidosis causes an inhibition of principal cell which therefore has less capacity to secrete K+ and buffer the ECF that contains excess K+ during acidosis

Question 55

What effect does alkalosis have on principal cell Na/K ATPase?

Answer 55

increases renal K+ secretion

Question 56

On a typical American diet, how much of H+ is added to the body?

Answer 56

~60 mEq/day

Question 57

108. Contrast the handling of K+ in cell types of the different regions of the nephron on a high K+ diet vs its handling on a low K+ diet.

Answer 57

K+ is freely filtered and almost (90%) completely reabsorbed in the proximal tubules and thick loop of Henle, if the body is trying to conserve K+ additional amounts can be reabsorbed by the collecting ducts; if the kidney is trying to void K+ large amounts of K+ are secreted into the distal tubules

Question 58

111. Explain the common association between acidemia/alkalemia and hyperkalemia/hypokalemia.

Answer 58

Alkalemia is often associated with hypokalemia, academia is usually associated with hyperkalemia, changes in extracellular concentration of hydrogen ions lead to exchange of ions with cellular cations (primarily K+), and a low pH with concomitant cellular uptake of hydrogen ions often leads cells to dump potassium

Question 59

112. State the normal H+ level in the ECF, both in terms of the pH and the molar concentration. What is the importance of the ECF H+ level for body function?

Answer 59

Normal hydrogen ion concentration is 40 nmol/L, this level is critical for normal enzymatic processes to proceed ie. functional groups on membrane proteins protonate and deprotonate to change shape and action; hydrogen ions important in metabolic processes, secretion of GI tract, de novo acid creation for metabolic storage and changes in the production of carbon dioxide

Question 60

113. List the 4 principle processes that affect the body H+ concentration.

Answer 60

1) metabolism of dietary protein (adds protons) 2) metabolism of dietary weak acids (adds conjugate base to the system) 3) GI secretions (H+ in gastric acid and bicarb in intestinal secretions) and 4) anaerobic metabolism of carbs and fats (lactic acid or ketone bodies add to acidic load) *** 5) additionally lactated ringers in intravenous solution add lactate (conjugated base)

Question 61

114. Write the equilibrium reaction equation for the most important pH buffer system in the body, and note the enzyme that is essential for enabling rapid reversibility of this reaction.

Answer 61

CO2+ H2O <> HCO3- + H+ (converted by carbonic acid)

Question 62

115. Identify the organ system responsible for regulation of levels of the weak acid in the reaction above, and also identify the organ system responsible for regulation of the conjugate base.

Answer 62

CO2 considered a weak acid is managed by the respiratory system
Bicarbonate considered the conjugate base is managed by the kidneys

Question 63

116. Differentiate the effects on acid/base balance of a diet high in meat vs a diet high in fruits and vegetables.

Answer 63

Proteins contain some amino acids that contribute to acid or base, sulfur-containing amino acids and those with cationic side chains are metabolized to CO2 and water and urea, the end result is fixed acid and metabolism of amino acids with anionic side changes add base

Citrus fruits can contain weak acids, organic acids in the protonate form and base form, although the pH is low there are far more base than free hydrogen ions and the result is addition of a base

Question 64

117. Explain how vomiting and diarrhea can affect the pH balance of the body.

Answer 64

Vomiting- excess loss of gastic acid, diarrhea- excess loss of intestinal bicarbonate

Question 65

118. Explain how anaerobic metabolism of carbohydrates and fat can affect the pH balance of the body.

Answer 65

Anaerobic metabolism of carbohydrate produces a fixed acid (lactic acid) along with the metabolism of triglyceride to ketone bodies, these processes don’t normally add much to the acid load but can add a huge acid load in unusual metabolic conditions

Question 66

119. Draw a proximal tubule cell, showing the mechanisms that allow the cells to reabsorb filtered HCO3-.

Answer 66

water and carbon dioxide are combined in a tubule cell, the bicarb is exported to the basolateral membrane and the H+ is exported out of the apical membrane to neutralize HCO3- in the filtrate “recovery of old bicarb” just maintains buffer system

Question 67

120. Draw a type A intercalated cell of the cortical collecting duct, showing the mechanisms that allow it to secrete protons.

Answer 67

Type A cells possess a primary active H/K ATPase which simultaneously move hydrogen ions into the lumen and potassium into the cells (actively) this transport system differs from the earlier transport system that couples Na+ with bicarb

Question 68

121. Draw a type B intercalated cell of the cortical collecting duct, showing the mechanisms that allow it to secrete HCO3-

Answer 68

basolateral membrane exit step for bicarbonate generated when H ions are secreted via the Cl-HCO3 antiporters or the Na-HCO3 symporters (both movement down electrochemical gradient) , this system creates a new H+ when the body is too alkaline

Question 69

122. Contrast the regional handling of HCO3- by the nephron when a person is either alkalotic or acidotic.

Answer 69

The PCT reabsorbs 80-90% of the filtered bicarbonate, thick ascending limb of Henle’s loop reabsorbs another 10% and almost all the remaining bicarbonate is reabsorbed b the distal convoluted tubule and collecting duct system NOTE: carbonic anhydrase is also located in the lumen facing surface of apical cell membranes, catalyzing the intraluminal generation of CO2 and water from secreted bicarb and H

Question 70

Define renal clearance.

Answer 70

the volume of PLASMA per unit time from which all of a substance is removed by the kidney and excreted in the urine

Question 71

Describe renal plasma clearance in an equation.

Answer 71

RPC= (Ux x V)/ Px

Question 72

135. State the units commonly used for renal plasma clearance.

Answer 72

mL/ hr

Question 73

134. Define and distinguish between “half-life,” “metabolic clearance rate,” and “renal clearance.”

Answer 73

metabolic clearance is a measure of the overall rate that a substance is removed from the body, by all routes, half life describes how long it takes for the concentration of a substance in the plasma to drop from its original concentration to one-half of that concentration and renal clearance when the kidney removes substance from the blood

Question 74

136. Given the urine flow rate and the plasma and urine concentrations of a given substance, calculate the renal clearance for that substance.

Answer 74

the rate at which the kidney clears a substance from the blood can be expressed in several ways: excreted load, or the renal plasma clearance is calculated by the following equation RPC = U x V / P

Question 75

137. Explain what aspect of renal function can be experimentally determined by measuring the renal plasma clearance of inulin, and what properties of the renal handling of inulin make this possible.

Answer 75

the renal clearance of inulin can be used to calculate GFR as inulin is freely filtered and is neither reabsorbed or secreted

Question 76

138. Explain what aspect of renal function can be experimentally determined by measuring the renal plasma clearance of para-aminohippurate (PAH), and what properties of the renal handling of PAH make this possible.

Answer 76

measuring renal plasma clearance of the substance PAH allows estimation of the total amount of blood flow through the kidneys because the kidney does not freely filter PAH but is actively secreted as it passes the proximal tubule that virtually all of the plasma flowing through the kidney is cleared of PAH therefore RPC pah = (Upah x V)/ Ppah

Question 77

139. Explain how comparing a known GFR to the renal clearance of a given freely filtered substance provides information about how that substance is handled.

Answer 77

renal clearance measurements allow us to see how a normal kidney handles new substances. knowing the plasma concentration, urine flow, and urine concentration and making educated judgements about whether the a substance is filterable you can make inferences about how a substance is hundred by the kidney

Question 78

140. Explain what aspect of renal function can be experimentally determined by measuring the renal plasma clearance of creatinine, and what properties of the renal handling of creatinine make this possible.

Answer 78

a more convent way to assess GFR is to measure renal plasma clearance of creatinine, creatinine is produced at fairly constant rate by the breakdown of muscles and a single measure meant of plasma creatinine contraption accompanied by a 34-hour determination of urinary flow rate and creatinine concentration can give a fairly good estimate of GFR,. the handling of creatinine by the kidney is similar to that inulin, it is freely filtered and not reabsorbed

Question 79

141. Explain why the plasma creatinine concentration can be used to reliably determine whether a person’s GFR is changed from the normal rate.

Answer 79

creatinine is produced at fairly constant rate by the breakdown of muscles

Question 80

142. Given the Cockcroft-Gault formula and necessary laboratory data for a patient, provide an estimate of her GFR.

Answer 80

GFR = [(140 -age in years) x weight]/ (72 [Pcr]) x.85 if patient is female