Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Renal Module > Lecture 3 - Nephron Segments And Tubular Transport > Flashcards

Lecture 3 - Nephron Segments And Tubular Transport Flashcards

1
Q

What is nephron endowment?

A

Born with the total number of nephrons you can’t get anymore, which is why premature babies are at more risk of kidney diseases, as they wont have as many a baby that was born at the correct time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How many nephrons does each kidney have?

A

On average around 1 million

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How is the GFR measured?

A

Glomerular filtration - measured in different ways:
Inject someone with insulin and measure how fast it goes through the kidney and this gives you a measure for GFR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the best indicator for GFR?

A

The calculated clearance of Creatinine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are some others way you can measure GFR except from insulin?

A

Have a blood test, or measure the concentration of creatinine which is the product of day muscle breakdown.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the test for concentration of creatinine?

A

Serum creatinine or plasma creatinine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What does it mean if creatinine is high?

A

Normally means that your kidney is not filtering properly.
Could mean, kidney failure, kidney disease or a urinary track obstruction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

In a healthy person is creatinine filtered out of the blood?

A

Yes Creatinine is filtered out. After these waste products are filtered they are found in the urine - it is considered a waste product

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is a normal eGFR?

A

Normally over 90 is considered normal, anything below 59 is considered to be an early sign of kidney disease?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How much does the kidney filter a day?

A

120ml on average GFR x 60 x 24 = 180 L per day

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Does alcohol affect the kidney?

A

No, it is a mild diuretic - it will not contribute to kidney disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does the kidney make?

A

The kidney makes renin, another hormone called erythropoietin and even vitamin D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a symptom of kidney failure?

A

The patient may become anemic as they are not producing enough of the erythropoietin hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What animal has the longest loop of henle?

A

The desert rate - it is able to produce a hyper concentrated urine which is far more concentrated than its blood minimising the need for excessive water intake - due to the long loops of henle. (Open university: the desert environment)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does the body react to being able to not urinate while running a marathon?

A

Due to the ADH - plays a crucial role in maintaining fluid balance during exercise. - decreases the amount of urine that flows in the bladder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the busiest nephron segment?

A

The proximal tubule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens if the filters in the PCT are damaged?

A

There will be lots of albumin in the blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Can the PCT filter albumin?

A

Yes but only tiniest bit the rest of it doesn’t pass through

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What can the PCT filter?

A

Water, glucose, Na+, K+, Cl-, phosphate, urate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the PCT?

A

It is the filtration unit of the kidney, contains the filtration barrier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the kidneys full of?

A

Mitochondria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What do the mitochondria do in the kidneys?

A

They are energy producing organelles but also respond to kidney-injury induced oxidative stress and inflammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What happens if a drug that is prescribed to a patient poisons the mitochondria?

A

You will get a serve phenotype - in the urine there will be extra phosphate or uric acid which is a sing that the PCT tubules are not functioning properly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What does Bicarboante combine with?

A

With a protein via an enzyme called carbonic anhydrase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How much bicarbonate reabsorption is filtered in the PCT?

A

80% - it is converted to lipid-soluble CO2 by apical carbonic anhydrase allowing to be absorbed.
It has a net effect so the process goes round in circles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Why do you measure urine glucose?

A

To know how high the serum glucose is

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are the 2 transporters for glucose reabsorption?

A

SGLT2 and SGTL1

28
Q

What does SGLT2 do?

A

Combined with Na+ and Glucose into the cell - 98% of glucose is taken up with this transporter

29
Q

What does SGLT1 do?

A

Takes up the last 2% of glucose

30
Q

Why may some patients have glucose in the urine?

A

May have a mutation in the transporter - so the transporters aren’t being as efficient

31
Q

Why are SGLT2 inhibitors so important?

A

They are the biggest thing to happen in the last 30 years - initially used in diabetics, peeing out extra glucose will help lower serum glucose. But also works with people who have kidney disease

32
Q

What is SGLT2?

A

It is a diuretic - wasting glucose pulls water along with it - but it is very expensive

33
Q

What can SGLT2 do?

A

Lowers blood pressure and reduces the pressure on the kidneys and the heart, changes the pressure of filtration

34
Q

What is suggested to be used with an ACE inhibitor?

A

SGLT2

35
Q

How does an ACE inhibitor work?

A

They work by blocking an enzyme that produces a hormone called angiotensin II which causes blood vessel to narrow and raises blood pressure

36
Q

What are the side effects for SGLT2?

A

Increase risk of UTI, fungal infections like thrush

37
Q

Are amino acids reabsorbed in the nephron?

A

Yes - by different Na+/ amino acid cotransporters in the PCT. Most of the transporters can transport drugs

38
Q

What is the heterodimeric amino acid transporter?

A

SLC3A1, SLC7A9 which transports cystine and lysine - it is very important in the reabsorption of amino acids in the kidney

39
Q

What is albumin reabsorption?

A

The body has a mechanism for filtering and retrieving albumin. The mechanism is by a Endocytosis mechanism

40
Q

What does the reabsorbed albumin undergo?

A

It undergoes transcytosis

41
Q

What does the thick ascending limb do?

A

It has salt transport NOT water, it contains a major salt transport on the apical side (K+/Cl- transporter - NKCC2) it has a neutral charge

42
Q

What does Na+ control?

A

Blood pressure

43
Q

What happens to K+?

A

It gets recycled

44
Q

What is the net absorption for the thick ascending limb?

A

Na+ and Cl-

45
Q

What is a drug that interferes NKCC2?

A

Loop diuretics - it inhibits NKCC2, they increase urine flow.

46
Q

What are the tight junctions for the thick ascending limbs?

A

They are a group of proteins that form the tight junction complex, and can transport Mg2+ and Ca2+ in a paracellular route - transports solutes between cells

47
Q

What is nearly everything in the PCT?

A

It is transcellular - transports solutes through a cell

48
Q

What is a thiazide diuretic?

A

It is a common treatment/ tablet for hypertension

49
Q

What is the DCT?

A

It is responsible for maintaining the balance of potassium, sodium and calcium, pH. An important role in the absorption of many ions and in water reabsorption

50
Q

What does aldosterone do?

A

Increases Na+ reabsorption in the DCT

51
Q

How can bowel cancer be helped?

A

Some targeted drugs like cetuximab and panitumumab - are epidermal growth factor receptor inhibitors and could turn off the tumour. Changing the ability to manage Mg2+ (cancer research.co.uk)

52
Q

What is the calcium thermostat?

A

A calcium sensing receptor

53
Q

What does the calcium sensing receptor play a role in?

A

Regulating parathyroid hormone secretion and urinary calcium excretion

54
Q

What can happen if the calcium sensing receptor undergoes mutations?

A

Hypercalcaemia can occur

55
Q

What happens in the collecting duct?

A

Selective water absorption, it has the control for the final Na+

56
Q

What is found beyond the collecting duct?

A

Renal pelvis, ureter, bladder and urethra

57
Q

What happens to brown bears during hibernation in regards to its collecting duct?

A

It has reduced metabolic rates. The bears are able to conserve water during hibernation. A bears bladder is able to reabsorb most of the urine back to its body. The conversation of fluid helps the bear survive without drinking (rrbigbear.com)

58
Q

What do intercalated cells secrete?

A

They secrete acid

59
Q

What can happen if you eat a lot of meat?

A

Your pH will be acidic as meat tends to be acidic, the body needs to be able to secrete the acid by the intercalated cells

60
Q

Do people who are vegetarian need lots of intercalated cells?

A

They produce lots of alkaline, so the cells do not need to work as hard as someone who eats lots of meat

61
Q

What can the intercalated cells become?

A

They can become proton secreting or Bicarboante secreting

62
Q

What is the principle cell?

A

ENaC, one na+ goes in but because of the charge it has to swap the charge with either a proton or a K+ ion .

63
Q

What pore helps with water transport in the collecting duct?

A

Aqauporin 2 in the apical surface, and aqauporins 3 and 4 in the basolateral surface

64
Q

What are aqauporins helped by?

A

Aqauporins are helped by a hormones called vasosupression or ADH which help with insertion and retrieval of water

65
Q

What is Diabetes mellitus?

A

Diabetes in the urine - makes the urine sweet (glucose)

66
Q

What is diabetes insipidus?

A

It is a disease if you lose the ability to regulate Aquaporins- urine doesn’t tase of anything.

67
Q

ADH receptor mutations are ….

A

They are X linked - boys, common symptom is bed wetting

Renal Module (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions