Renal 9 Flashcards
1
Q
____ is a highly regulated ion via:
- Enzymes
- Blood clotting
- Muscle contraction
- Channels
A
H+
2
Q
What is the range that is compatible with life for only a short time for pH?
A
pH: 6.8-8.0
3
Q
The following are way to ____ H+ ions:
- Generation of H+ from CO2
- Production of nonvolatile acids from metabolism of proteins and other organic molecules
- Loss of HCO3 in diarrhea or other nongastric GI fluids
- Loss of HCO3 in urine
A
Gain H+ ions
4
Q
The following are way to ____ H+ ions:
- Utilization of H+ in the metabolism of various organic anions
- Vomit
- Urination
- Hyperventilation
A
Loss of H+ ions
5
Q
What is the net gain of H+ daily?
A
40-80 mEq/L
6
Q
______ acids are produced by metabolism of organic molecules
A
Non-volatile acids (Fixed)
7
Q
Adds ≈ 80 mEq/dayProtein Catabolism – sulfuric acid and HCl
Phospholipid Catabolism – phosphoric acid
Exercise, hypoxia – lactic acid
Post-absorptive state, diabetes mellitus – acetoacetic, β-hydroxy-butyric acids
Nucleoprotein metabolism – uric acid
A
Non-volatile acids (Fixed)
8
Q
Primary Systems Regulate the [H+] in Body Fluids
_____ system:
Acid-base buffer systems (body fluids)
“instantaneous”
A
Chemical system
9
Q
Primary Systems Regulate the [H+] in Body Fluids
_____ system:
Regulates the removal of CO2(and acid)
A
Respiratory system
10
Q
Primary Systems Regulate the [H+] in Body Fluids
_____ system:
Excrete an acidic or alkaline urine
A
Kidneys
11
Q
What are the 2 buffer systems used in the chemical system to regulate [H+] in body fluids in the ECF?
A
Bicarbonate buffer system and Phosphate buffer system
12
Q
Most Powerful EC BufferMost Powerful EC Buffer
CO2 and HCO3 regulated by respiratory regulated by respiratory and renal systems and renal systems
A
Bicarbonate buffer system
13
Q
Not a significant buffer for ECF
Concentration significantly lower than Bicarbonate system
Important for buffering renal tubular fluids and ICF
A
Phosphate buffer system
14
Q
_____% of the total chemical buffering of the body fluids is inside the cells
A
60-70%
15
Q
_____ system
Regulates the removal of CO2(and acid)
Change VA
Seconds to minutes (maximal in hours) “fast.”
A
Respiratory system
16
Q
Three processes facilitate ____ transport:
- 10% dissolved in plasma
- 25% binds to amino groups in Hb(carbaminohemoglobin)
- Remainder converted to H2CO3 by CA in erythrocytes.
A
CO2 transport
17
Q
In the respiratory system, changes in _____ can function to restore pH following acid/base disturbances
A
Alveolar ventilation
18
Q
Does hypoventilation increase or decrease pH?
A
Decreases
19
Q
Does hyperventilation increase or decrease pH?
A
Increases
20
Q
Does increased AV increase or decrease pH?
A
Increases pH
21
Q
Does decrease AV increase or decrease pH?
A
Decreases pH
22
Q
_____ is the most powerful of the acid/base regulatory systems
A
Kidneys
23
Q
Kidney regulate pH by altering plasma _____
A
[HCO3-]
24
Q
The ______:
–Secrete H+
–Reabsorb, produce, or excrete HCO3-
A
kidneys
25
99.9% of ______ is reabsorbed
[HCO3-]
26
______ % of HCO3-absorption - and H+ secretion - occurs in proximal tubule)
85%
27
(85% of HCO3-absorption - and H+ secretion - occurs in what nephron segment?
proximal tubule
28
For each _____ reabsorbed, a H+ must be secreted.
HCO3-
29
For each HCO3- reabsorbed, a ___ must be secreted.
H+
30
Secondary active transport pattern of H+secretion occurs in what segments of the nephron?
the proximal tubule, TAL, and the early distal tubule
31
___% of filtered HCO3-reabsorbed by secondary active transport process and requires 4000 mEq of H+ to be secreted
95%
32
Rate of tubule H+ secretion = _____ mEq/day
4400 mEq/day
33
HCO3-]ECF = _____ mEq/L)
24 mEq/L
34
Excrete _____ mEq/day of non-volatile acid produced by metabolism
80 mEq/day
35
In ______, HCO3-load > H+secretion and excess HCO3- will be excreted
Alkalosis
36
In Alkalosis, HCO3-load > H+secretion and excess ______ will be excreted
HCO3-
37
In _____, H+ secretion > HCO3-load and excess H+ excreted
Acidosis
38
In Acidosis, H+ secretion > HCO3-load and excess ___ excreted
H+
39
Excess H+ Excretion is a function of what part of the nephron?
Function of late DT and CD
40
Responsible for only 5% H+ secretion, but enough to create maximally acidified urine
Excess H+ secretion
41
____ and ______ systems are used for excess H+ excretion (non-volatile acids produced during metabolism).
Pi and glutamine/NH4+
42
Abnormal H+ production induces ________ compensation
renal compensation
43
Where in the nephron is the phosphate buffer system acting?
Early nephron
44
When secreted H+ exceeds filtered load of HCO3-, H+can bind to _______
Phosphate buffer
45
Anytime H+ combines with a buffer other than HCO3-, results in new _____ being added to the ECF
HCO3-
46
Anytime ____ combines with a buffer other than HCO3-, results in new HCO3-being added to the ECF
H+
47
Most filtered ____ reabsorbed so only small amount of this buffer available to interact with H+ in filtrate.
Pi
48
In what sections of the nephron, NH4+ is added to filtrate following glutamine metabolism and represents acid secretion
PT, TAL and DT
49
In PT, TAL and DT, ____ is added to filtrate following glutamine metabolism and represents acid secretion
NH4+
50
In PT, TAL and DT, NH4+ is added to filtrate following ______ metabolism and represents acid secretion
glutamine
51
In what segment of nephron is, NH3 is secreted into lumen where it combines with H+ to form NH4+
CD
52
In CD, ____ is secreted into lumen where it combines with H+ to form NH4+
NH3
53
In CD, NH3 is secreted into lumen where it combines with H+ to form _____
NH4+
54
When there is excess H+ buffered and excreted, this results in new _____ being added to the ECF
HCO3
55
____ buffer system: Responsible for 50% of the acid excreted and 50% of new HCO3-added to ECF
Ammonia Buffer System
56
In PT, TAL and DT, NH4+ is added to filtrate following glutamine metabolism and represents acid secretion
In CD, NH3 is secreted into lumen where it combines with H+ to form NH4+
Results in new HCO3-being added to the ECF
Responsible for 50% of the acid excreted and 50% of new HCO3-added to ECF
Ammonia Buffer System
57
_____ secretion by tubular epithelium necessary for:
HCO3- reabsorption
Addition of new HCO3-to ECF
Acid Excretion
Rate of secretion must be carefully controlled to maintain acid-base homeostasis
H+ secretion
58
Under Normal Conditions: Acid secretion needs to be enough to do what 2 things?
Reabsorb almost all filtered HCO3-
| Rid the body of non-volatile acids produced during metabolism
59
During _____: Acid secretion decreased
Alkalosis
60
During Alkalosis: Acid secretion _____
decreased
61
```
During _______:
Not all filtered HCO3-is reabsorbed
HCO3-is excreted
No NH4+ or H2PO4-
-No non-volatile acid excreted-No new HCO3-
- added to ECF
```
Alkalosis
62
During _____: Acid secretion is increased
Acidosis
63
During Acidosis: Acid secretion is ______
increased
64
```
During ______:
Almost all filtered HCO3-is reabsorbed
NH4+ and H2PO4- generated
-Acid excreted
-New HCO3-added to ECF
```
Acidosis
65
What are the Two Most Important Stimuli that increase H+ secretion by tubules?
1. Increase in PCO2 of ECF
| 2. Increase [H+]ECF
66
Does an increase or decrease in PCO2 increase H+ secretion and HCO3- reabsorption?
Increase
67
Does an increase or decrease in H+ increase H+ secretion and HCO3- reabsorption?
Increase
68
Does an increase or decrease in HCO3 increase H+ secretion and HCO3- reabsorption?
decrease
69
Does an increase or decrease in Ang II increase H+ secretion and HCO3- reabsorption?
Increase
70
Does an increase or decrease in aldosterone increase H+ secretion and HCO3- reabsorption?
Increase
71
Does hypokalemia increase or decreaseH+ secretion and HCO3- reabsorption?
Increase
72
Does an increase or decrease in aldosterone decrease H+ secretion and HCO3- reabsorption?
Decrease
73
Does an increase or decrease in Ang II decrease H+ secretion and HCO3- reabsorption?
Decrease
74
Does an increase or decrease in H+ decrease H+ secretion and HCO3- reabsorption?
Decrease
75
Does an increase or decrease in HCO3- decrease H+ secretion and HCO3- reabsorption?
Increase
76
Does an increase or decrease in PCO2 decrease H+ secretion and HCO3- reabsorption?
Decrease
77
Does hyperkalemia increase or decrease H+ secretion and HCO3- reabsorption?
Decrease
78
Problems with ventilation or gas exchange
Ex. Hypoventilation, Pulmonary Edema, COPD, Damage to respiratory centers in brain stem
Increased PCO2
1.Respiratory Acidosis
79
_______ compensation:
Buffer of body
Renal Compensation
Reabsorb all Filtered HCO3- Reabsorb all Filtered
HCO3-
Secrete Excess H+ and add New HCO33- to ECF
(increased glutamine metabolism and NH metabolism
and NH4+ excretion)
Respiratory acidosis
80
All changes in pH not associated with an increase in CO2 levels
1. Failure of kidney to excrete metabolic acids (Renal Failure, Addison’s Disease)
2. Formation of excess quantities of metabolic acid (ketoacidosis)
3. Increased input of of metabolic acids (aspirin and methyl alcohol)
4. Loss of base from body (Diarrhea)
Metabolic Acidosis
81
_____ compensation:
Renal Compensation (Assuming this isn't the problem)
Reabsorb all Filtered HCO3- Reabsorb all Filtered
HCO3-
Secrete Excess H+ and add New HCO33- to ECF
(increased glutamine metabolism and NH metabolism
and NH4+ excretion)
Respiratory Compensation
Compensatory increase in VA in response to
metabolic acid (hyperventilation)
Metabolic Acidosis
82
______
Rare
Excessive ventilation Ex. Hyperventilation
Leads to Decreased PCO2
Respiratory Alkalosis
83
______ compensation:
- Renal Comp
- Increased HCO3-
- Decreased H+ excretion
Respiratory Alkalosis
84
_______
All changes in pH not associated with a decrease in CO2 levels
1.Diuretics
2.Excess Aldosterone
3.Excessive vomiting
4.Ingestion of Alkaline drugs (ex. NaHCO3-)
4. Metabolic Alkalosis
85
_____ compensation:
- Respiratory Compensation
- Compensatory decrease in VA in response to metabolic acid
Respiratory Alkalosis
86
The following are responses to ______:
- Sufficient H+ is secreted to reabsorb all filtered HCO3-
- Still more H+ is secreted and this contributes new HCO3- to the plasma as the H+ is excreted bound to non bicarbonate urinary buffers such as HPO4-
- Tubular glutamine metabolism and ammonium excretion are enhanced which also contributes new HCO3- to the plasma
Acidosis
87
In acidosis, the urine is highly _____
Acidic
88
The following are responses to ______:
- Rate of hydrogen ion secretion is inadequate to reabsorb all the filtered HCO3- so significant amounts of HCO3- are excreted in the urine, and there is little or no excretion of H+ on non bicarbonate urinary buffers
- Tubular glutamine metabolism and ammonium excretion are decreased so that little or no new HCO3- is contributed to the plasma from this source
Alkalosis
89
In alkalosis, the urine is highly ______
Alkaline
90
In which disorder are the following conditions true?
- Increased H+
- Increased HCO3-
- Increased CO2
Respiratory acidosis
91
In which disorder are the following conditions true?
- Decreased H+
- Decreased HCO3-
- Decreased CO2
Respiratory alkalosis
92
In which disorder are the following conditions true?
- Increased H+
- Decreased HCO3-
- Decreased CO2
Metabolic acidosis
93
In which disorder are the following conditions true?
- Decreased H+
- Increased HCO3-
- Increased CO2
Metabolic alkalosis
94
If pH is <7.4, HCO3- <24 mEq/L, and PCO2 <40 mm Hg?
Metabolic acidosis
95
If pH is <7.4, HCO3- >24 mEq/L, and PCO2 >40 mm Hg?
Respiratory acidosis
96
If pH is >7.4, HCO3- <24 mEq/L, and PCO2 <40 mm Hg?
Respiratory alkalosis
97
If pH is >7.4, HCO3- >24 mEq/L, and PCO2 >40 mm Hg?
Metabolic alkalosis
98
What is the main compensation for metabolic acidosis?
Respiratory: Hypervent
99
What is the main compensation for respiratory acidosis?
Renal: Increased HCO3 in ECF
100
What is the main compensation for metabolic alkalosis?
Respiratory: Hypovent
101
What is the main compensation for respiratory alkalosis?
Less H+ excretion; Increased HCO3 secreting
