Lec 19,20,20: Renal Physiology

Front 1

Kidneys receive ___ mL blood/min at rest. This is __% of CO, and they produce a minimum of __L of urine per day.

Back 1

1000 mL/min of blood. 20% of CO; 500 mL of urine per day

Front 2

How do kidneys maintain water and electrolyte balance, and plasma volcume?

Back 2

Compensate for 1) ingested water and salts 2) abnormal water loss 3) Maintain constant osmolarity (300 mOsm)

Front 3

Average pH of ECF and ICF

Back 3

7.4; helped maintained by kidneys

Front 4

How do kindeys function as an endocrine gland?

Back 4

Produce EPO

Front 5

Metabolic functions of Kidney

Back 5

Convert Vitamin D into its active Form

Front 6

What is Vitamin D?

Back 6

Cholesterol-like compound produced in skin in response to sunlight, but it has to be activated in chemical reactions.

Front 7

Where is vitamin D activated into its active form?

Back 7

One reaction occurs in liver; one in kidney

Front 8

T/F: Active Vitamin D promotes re-absorption of Ca++ and PO34 from intestines.

Back 8

FALSE; absorbtion

Front 9

T/F: Active Vitamin D promotes extrection of Ca++ and PO34 from intestines.

Back 9

False; promotes ABSORBTION

Front 10

T/F: Active Vitamin D promotes absorption of Ca++ and PO34 from intestines.

Back 10

True

Front 11

Vitamin D Deficiency results in what condition?

Back 11

Impaired ability to absorb Ca++, so PTH stimulates mobilization of Ca++ from bones into ECF and ICF

Front 12

T/F: PTH stimulates mobilization of Ca++ from bones into ECF and ICF.

Back 12

True

Front 13

During a vitamin D deficiency, bones can become soft and weak. What conditions does this cause?

Back 13

rickets in kids; osteomalacia in adults

Front 14

Renin is an ___. It affects __ retention by the kidneys.

Back 14

Enzyme produced by kidneys; Na+ retention in kidneys

Front 15

What is a nephron?

Back 15

functional unit of the kidney; responsible for urine formation

Front 16

There are 1 thousand/1 million/10 million nephrons per kidney.

Back 16

1 million

Front 17

Describe the components of a nephron.

Back 17

Vascular components (blood vessels) and tubular components (tubules that hold "filtrate" that eventually becomes urin)

Front 18

The afferent arteriole carries blood from _____ to _____.

Back 18

Renal artery; glomerulus

Front 19

T/F: Afferent arteriole carries blood from renal artery to glomerulus.

Back 19

True

Front 20

T/F: Efferent arteriole carries blood from renal artery to glomerulus.

Back 20

False; afferent artery

Front 21

The glomerulus is a ball of ____. The walls of the ___ have __ pores, which are ____ times more permeable than a ____.

Back 21

ball of CAPILLARIES. WALLS OF CAPILLARIES have PORES 100x's more permeable than pores of normal capillary

Front 22

Plasma filters out of _____ into the tubular components of the nephron.

Back 22

Glomerulus capillaries

Front 23

T/F: Blood cells and large proteins are filtered to tubular components of nephron.

Back 23

False; they are too big; so they stay int he blood

Front 24

First step in urine formation

Back 24

Glomerular filtration

Front 25

How much of the plasma of the blood that enters the glomerulus gets filtered in the tubular component of the nephron?

Back 25

20%

Front 26

T/F: The majority of the blood gets filtered to tubular portion of nephron.

Back 26

False; 20%

Front 27

Normal GFR.

Back 27

125 mL of filtrate/min; 180 L of filtrate produced per day

Front 28

How much filtrate is produced per day by G. filtration?

Back 28

180 L

Front 29

T/F: Substances such as caffeine increase urine output by increasing GFR.

Back 29

True

Front 30

T/F: Substances such as caffeine increase urine output by decreasing GFR.

Back 30

False; increase GFR

Front 31

T/F: Filtrate has same constitutents as plasma except it lacks plasma proteins (some small proteins do enter the filtrate but they are usually reabsorbed by proximal tubule, so urine is usually protein free).

Back 31

True

Front 32

T/F: Filtrate has same constitutents as plasma except it lacks all plasma proteins.

Back 32

False; some proteins remain in filtrate but are usually reabsorbed by proximal tubule.

Front 33

T/F: Filtrate has same constitutents as plasma except it lacks plasma proteins (some small proteins do enter the filtrate but they are usually reabsorbed by distal tubule, so urine is usually protein free).

Back 33

False; proximal tubule

Front 34

The efferent artery conducts blood where?

Back 34

From Glomerulus to Peritubular capillaries

Front 35

T/F: The efferent artery conducts blood from glomerulus to peritubular capillaries.

Back 35

True

Front 36

This allows for exchange of materials between vascular and tubular components of the nephron.

Back 36

Peritubular capillaries

Front 37

T/F: The distal tubule allows for exchange fo material ebtween vasc and tub portions of neuron.

Back 37

False; peritubular capillaries do that!

Front 38

T/F: The peritubular cavities supply the renal tissue with blood.

Back 38

True

Front 39

Supplies renal tissue with blood

Back 39

Peritubular cavities

Front 40

Closely assoiciated with tubular compnents of nephron.

Back 40

Peritubular capillaries

Front 41

T/F: The efferent arteriole is closely associated with tubular comonents of nephron.

Back 41

False; peritubular capillaries

Front 42

The Vasa Recta is a specialized portion of the ____ that lies in close association with ____.

Back 42

Specialiezed portion of the PERITUBULAR CAPILLARIES; close asosciation with Loop of Henle

Front 43

T/F: The Vasa Recta is a specialized portion of the peritubular capillaries that lies in close association with the Loop of Henle.

Back 43

True

Front 44

T/F: The Vasa Recta is a specialized portion of the peritubular capillaries that lies in close association with the distal tubule.

Back 44

False; loop of Henle

Front 45

The Bowman's capsule does what?

Back 45

Collects filtrate from Glomerulus; connects with Proximal Tubule

Front 46

T/F: Proximal tubule is very important in reabsorption of important substances back into the blood.

Back 46

True

Front 47

T/F: Proximal tubule is very important in secretion of important substances back into the tubule.

Back 47

False; importnat in reabsorption

Front 48

Describe reabsorption in proximal tubule.

Back 48

67% of Na+ is actively reabsorbed; Majority of Cl- is reabsorbed (follows Na_ due to electrical charge); All K+ is reabsorbed actively; 65% of water is reabsorbed passively (osmosis); all proteins and glucose are actively reabsorbed.

Front 49

Which substances are actively reabsorbed in prox. tubule? Passively?

Back 49

Active: 65% of Na+, All of K+, All glucose and amino acids
Passive: Most Cl- (follows Na+ due to charge), 65% of water (osmosis)

Front 50

T/F: Water and Cl- are passively reabsorbed in prioximal tubule.

Back 50

True

Front 51

T/F: In the prox tubule, amino acids and glucose are reabsorbed unless they reach the renal thresold in plasma (high concentrations) and start appearing in urine.

Back 51

True

Front 52

When do gluclose and AA's start appearing in urine?

Back 52

After reaching renal threshold (high concentrations)

Front 53

Most common endocrine disorder

Back 53

Diabetes Mellulitus

Front 54

T/F: Type I diabetes is due to inadequate insulin production.

Back 54

True

Front 55

T/F: Type II diabetes is due to inadequate insulin production.

Back 55

False; this is Type I

Front 56

T/F: Type II diabetes occurs when tissues become non-responsive to insulin.

Back 56

True

Front 57

Diabetes mellulitis causes glucose to appear in the urine since its levels are greater than its renal threshold.

Back 57

True

Front 58

Why does glucose appear in urine in Diabetes mellulitis?

Back 58

Its levels exceed renal threshold

Front 59

T/F: Renal thresholds of phosphate and calcium are equal to their plasma concentration.

Back 59

True

Front 60

T/F: Renal thresholds of phosphate and calcium are exceed that of their plasma concentration.

Back 60

False; equal to plasma concentration

Front 61

T/F: What causes the passive diffusion of urea down its concentration gradient in the proximal tubule?

Back 61

Concentration gradient caused by osmosis fo water

Front 62

T/F: 50% of urea is passively diffused back into blood as a result of concentration gradient produced by osmosis of water into interstitial space.

Back 62

True

Front 63

T/F: It is advantageous to reabsorb urea in the blod.

Back 63

False; it is not; but it is not enough to cause problems in healthy individuals with normal GFR.

Front 64

What doehigh blood urea indicate?

Back 64

renal failure; abnormal GFR

Front 65

T/F: If blood is too acidic, H+ is secreted into the tubule.

Back 65

True

Front 66

T/F: If blood is too acidic, H+ is reabsorbed intto bloodl

Back 66

False; blood is secreted into prox. tubule

Front 67

The LoH dips from ___ to the ___.

Back 67

cortex to medulla

Front 68

T/F: The descending LoH is permeable to water, but has no active pumping of Na+ or Cl-.

Back 68

True

Front 69

T/F: The ascending LoH is permeable to water, but has no active pumping of Na+ or Cl-.

Back 69

False; this is the DESCENDING

Front 70

T/F: The ascending LoH is not permeable to water, but it has active pumping of Na+ (primary active transport) and Cl- (secondary active transport) out of tubule and into ECF.

Back 70

True

Front 71

T/F: The descending LoH is not permeable to water, but it has active pumping of Na+ (primary active transport) and Cl- (secondary active transport) out of tubule and into ECF.

Back 71

False; ASCENDING

Front 72

T/F: The ascending LoH is permeable to water, and it has active pumping of Na+ (primary active transport) and Cl- (secondary active transport) out of tubule and into ECF.

Back 72

False; not permeable to water

Front 73

T/F: The ascending LoH is not permeable to water, but it has active pumping of Na+ (secondary active transport) and Cl- (primary active transport) out of tubule and into ECF.

Back 73

False; Na+ is primary AT, Cl- is secondary AT

Front 74

Osmotic pressure increases in _____ and decreases ____.

Back 74

ECF of kidney medulla; ascending loop of henle

Front 75

T/F: osmotic pressure increases in kidney cortex, but decreases in the loop of henle.

Back 75

False; increases in kidney medulla

Front 76

T/F: In the loop of henle, as fluid reaches the top of the ascending loop, it becomes dilute (100 mOsm) due to pumpoing of Na+ and Cl- out of the tubule.

Back 76

True

Front 77

T/F: In the loop of henle, as fluid reaches the top of the descending loop, it becomes dilute (100 mOsm) due to pumpoing of Na+ and Cl- out of the tubule.

Back 77

False; top of ASCENDING loop

Front 78

T/F: In the loop of henle, as fluid reaches the top of the ascending loop, it becomes concentrated.

Back 78

False; it becomes dilute (100 mOsm) due to pumping of Na and Cl.

Front 79

The high levels of NaCl in kidney's interstitial fluid do what?

Back 79

Attact water from descending loop of henle; incerasing oSM in bottom of the loop to 1200 mOsm.

Front 80

T/F: the high NaCl levels in interstitial fluid attact water from descending LoH, which makes osM in bottom of loop 1200 mOsm.

Back 80

True

Front 81

T/F: the low NaCl levels in interstitial fluid attact water from descending LoH, which makes osM in bottom of loop 1200 mOsm.

Back 81

FAlse; HIGH NaCl levels

Front 82

T/F: the high NaCl levels in the lumen attact water from descending LoH, which makes osM in bottom of loop 1200 mOsm.

Back 82

False; high NaCl levels in interstitial fluid

Front 83

Describe osmotic gradient in kidneys.

Back 83

Blood=300 mOsm; cortex=300 mOsm; medulla=1200 mOsm

Front 84

What does the osmotic gradient allow kidneys to do?

Back 84

Concentrate or dilute urine when necessary

Front 85

T/F: The mOsM in the kidney's medulla is 300 mOsm.

Back 85

False; medulla=1200 mOsm

Front 86

T/F: the vasa recta supplies blood to the LoH by interrputing its osmotic gradient. it generates a countercurrent.

Back 86

False; DOES NOT interrupt osmotic gradient!

Front 87

Aldosterone controls the reabsorption of __ and secretion of ___.

Back 87

Na+/K+

Front 88

T/F: In the Collecting Duct and Distal tubule, aldosterone always causes reabsorption of Na+ and secretion of K+.

Back 88

FAlse; only when needed

Front 89

T/F: In the LoH and Distal tubule, aldosterone always causes reabsorption of Na+ and secretion of K+.

Back 89

FAlse; collecting duct and distal tubule

Front 90

T/F: In the collecting duct and distal tubule, reabsprotion of Na+ and secretion of K+ is an active process.

Back 90

True

Front 91

T/F: In the CD and DT, H+ can be secreted depending on conditions.

Back 91

True

Front 92

T/F: In the CD and DT, H+ can be reabsorbed depending on conditions.

Back 92

False; can be SECRETED

Front 93

T/F: In the CD and DT, H2O is passively reabsorbed; conrolled by ADH.

Back 93

True

Front 94

T/F: In the Proximal Tubule, H2O is passively reabsorbed; conrolled by ADH.

Back 94

False; Distal tubule and collecting duct

Front 95

In the distal tubule and collecting duct, what does ADH do?

Back 95

Causes passive re-absorption of H2O if needed

Front 96

T/F: The colelcting duct functions the same as the distal tubule in regards to collection/secretion.

Back 96

True;

Front 97

ADH is produced by the ___ and released by the ___.

Back 97

hypothalamus; posterior pituitary

Front 98

What does ADH do to distal tubule and connecting duct?

Back 98

Increases water permability of them; increases water channels in membranes so water flows out osmotiically; decreases urine concentraiton.

Front 99

With High ADH, what happens to fluid in tubules?

Back 99

It's concentrated as it travels down medulla; it becomes concentrated to up to 1200 mOsm

Front 100

T/F: Without ADH present, tubules are still permeable to water.

Back 100

False; tehy are not permeable to water

Front 101

T/F: With no ADH present, fluid in tubules stays dilute (100 mOsm) and travels through distal and CT.

Back 101

True

Front 102

T/F: With high ADH present, fluid in tubules stays dilute (100 mOsm) and travels through distal and CT.

Back 102

FAlse; occurs when No ADH is present

Front 103

T/F: Ethanol increaes ADH levels, which can cause dehydration.

Back 103

False; ethanol decreaes ADH levels, which causes increaed production of dilute uruine. More liquid leaves the body than enters it, which can cause dehydration.

Front 104

T/F: Ethanol decreases ADH levels, which can lead to inc. production of dilute urine.

Back 104

True

Front 105

Diabetes insipidus refers to what?

Back 105

Inability to form concentrated urine

Front 106

T/F: Diabetes mellulitis is caused by the inability to form concentrated urine.

Back 106

False; this is diabetes insipidus

Front 107

What causes Diabets inspidius?

Back 107

Decrease in ADH production

Front 108

T/F: Diabetes inspipdius is caused by incrase in ADH, which causes fluid loss of 5-10 mL per day.

Back 108

Fasle; DECREASE in ADH causes fluid loss

Front 109

Treatment for diabetes inspidus.

Back 109

Nasal spray with synthetic ADH.

Front 110

Renin is an enzyme produced by cells in the ___.

Back 110

juxtoglomular apparatus of kidney

Front 111

T/F: Renin is an enzyme produced by cells in the distal tubule of the kidney.

Back 111

False; juxtoglomular apparatus of kidney

Front 112

T/F: The juxtoglomular apparatus is a combination of vascular and tubular components.

Back 112

True

Front 113

T/F: Renin is produced by granular cells in JGA.

Back 113

True

Front 114

T/F: Renin is produced by smooth cells in JGA.

Back 114

False; granular

Front 115

Renin is produced in response to what 3 factors?

Back 115

1) decrased NaCl, decreased blood pressure, decreased fluid volume

Front 116

T/F: Renin is produced in response to incrased blood volume, increased blood pressure, or decrased NaCl.

Back 116

False; decreased NaCl, decreased fluid volume, decraesd BP.

Front 117

Renin converts angiotensinogen to _____.

Back 117

Angiotensin I

Front 118

T/F: Renin converts angiotensinogen (a plasma protein produced by the liver) into angiotensin I.

Back 118

True

Front 119

T/F: Renin converts angiotensinogen (a plasma protein produced by the lungs) into angiotensin I.

Back 119

False; liver

Front 120

T/F: Renin converts angiotensinogen (a plasma protein produced by the liver) into angiotensin II.

Back 120

False; angiotensin I

Front 121

Angiotensinogen is what

Back 121

Plasma protein produced by the liver

Front 122

____ converts angiotensin I into angiotensin II.

Back 122

ACE (angiotension converting enzyme) produced in lungs

Front 123

T/F: ACE (angiotensin converting enzyme, produced in the lungs) converts angiotensin I into angiotensin II.

Back 123

True

Front 124

ACE (angiotensin converting enzyme, produced in the liver) converts angiotensin I into angiotensin II.

Back 124

False; produced in lungs

Front 125

Angiotensin II Stimulates relaease of what: From where?

Back 125

Aldosterone from adrenal corex (steroid hormone)

Front 126

T/F: The release of aldosterone (steroid hormone) from the adrenal cortex is initiated by angiotensin II.

Back 126

True

Front 127

T/F: The release of aldosterone (steroid hormone) from the posterior pituitary is initiated by angiotensin II.

Back 127

False; adrenal cortex

Front 128

T/F: Angiotensin II stimulates vasoconstrnction

Back 128

True

Front 129

T/F: Angiotensin I stimulates vasoconstrnction

Back 129

False; Angiotensin II

Front 130

T/F: Angiotensin II stimulates vasodilation

Back 130

Flalse; vasoconstriction

Front 131

T/F: Aldosterone stimulates vasoconstriction.

Back 131

False; Angiosterin II.

Front 132

T/F: Aldosterone increases the numbers and pumps of ion channels. Na+ is actively reabsprobed; Cl- passively follows. K+ is actively secreted via the Na+, K+ pump.

Back 132

True

Front 133

In the absence of aldosterone, ___ g of NaCl can be excreted per day.

Back 133

20 g

Front 134

T/F: In the abesnce of aldosterone, up to 20 g of NaCl can be excreted per day.

Back 134

T

Front 135

T/F: In the abesnce of aldosterone, up to 10 g of NaCl can be excreted per day.

Back 135

False; 20 g

Front 136

During max aldosterone production, __gf NaCl is given off in urine.

Back 136

no NaCl

Front 137

T/F: During max aldosterone production, 10g of NaCl is given off in urine.

Back 137

False; no NaCl

Front 138

Typical person who consumes salt gives __ g of NaCl daily.

Back 138

10g; recommendation is 2.4 g a day

Front 139

What do ACE inhibitors do?

Back 139

Block action of ACE; blocks production of Angiotensin II and preventing relase of aldosterone

Front 140

T/F: ACE inhibitors block action of ACE; which blocks angiotensin I which blocks the release of aldosterone.

Back 140

False; angiotensin II

Front 141

T/F: ACE inhibitors lower blood pressure by preventing Na+ reabsorption and decreasing H2O retention and blood volume.

Back 141

True

Front 142

T/F: ACE lowers blood pressure by preventing Na+ reabsorption and decreasing H2O retention and blood volume.

Back 142

False; ACE INHIBITORS do this!

Front 143

T/F: ACE inhibitors lower blood pressure by stimulating Na+ reabsorption and decreasing H2O retention and blood volume.

Back 143

False; PREVENTING Na+ reabsorption

Front 144

T/F: ACE inhibitors decrease vasocinstriction.

Back 144

True

Front 145

T/F: ACE inhibitors increase vasocinstriction.

Back 145

FAlse; decrease vasoconstriction

Front 146

Angiotensin II stimulates ___ to contract.

Back 146

smooth muscle in arteries

Front 147

T/F: endurance atheletes in warm water produce high amounts of aldosterone.

Back 147

True

Front 148

T/F: endurance atheletes in warm water produce low amounts of aldosterone.

Back 148

False; high aldosterone

Front 149

T/F: endurance atheletes in cold water produce high amounts of aldosterone.

Back 149

False; warm weather

Front 150

Production of excess aldosterone in athelestes in warm weather causes what?

Back 150

Prevents Na+ loss (enhances re-absorption).

Front 151

What do sports drinks do?

Back 151

Compensate for K+ loss brought on by aldosterone (which actively secretes K+)

Front 152

T/F: Sports drinks compensate only for K+ loss.

Back 152

False; Na_ and K_ loss

Front 153

T/F: Aldosterone has the same effect on sweat glands as it does on nephrons.

Back 153

True

Front 154

T/F: Aldosterone has the same effect on sebum glands as it does on nephrons.

Back 154

False; SWEAT glands