Fall Final Flashcards
1
Q
Seven functions of respiratory system
A
Provide oxygen Eliminate CO2 Regulate blood pH Facilitate speech Microbial defense Regulate chemical messengers in blood Defend against blood clots
2
Q
What structures are associated with the conducting or respiratory zones
Basic structure (tissue type)
Basic functions
A
Conducting:
Trachea -> primary bronchi -> secondary bronchi -> tertiary bronchi -> bronchioles -> terminal bronchioles
Warm air, parallel airways (minimize resistance), microbial protection
Respiratory:
Respiratory bronchioles -> alveolar ducts -> alveolar sacs
Airflow regulated by bronchiolar smooth muscle, alveoli optimize gas exchange, microbial defense by pulm Macrophages
3
Q
Genetic defect associated with cystic fibrosis
Consequences of the disease on respiratory function
A
Mutation in genetic code for Cl- channel
Na/Cl aren’t secreted across epithelium into mucous
Less water in mucous, becomes thick and dry
4
Q
Three types of cells found in an alveolus and functions
A
Type I - epithelial, gas exchange
Type II - secrete surfactant
Macrophages
5
Q
Properties of alveoli that increase respiratory surface area and enhance gas exchange
A
High surface area
Vascularization
Thin respiratory surface
Low rate of bloodflow for more time
6
Q
Components of alveolar-capillary interface (what does a gas molecule pass through)
Diffusion rates in O2 vs CO2
A
Alveolus Apical membrane of Type I Cytoplasm Basal membrane of Type I Basal lamina Underlying connective tissue Basal membrane of endothelial cell Cytoplasm Apical membrane of endothelial cell Plasma
CO2 diffuses faster because it is more soluble
7
Q
Relationship of the lung to the pleural sac (contains intrapleural fluid)
Relationship to the thoracic cage
A
Fist in a fluid filled balloon
Outer pleura adheres to underside of thoracic wall
8
Q
Mathematical relationship b/t airflow, pressure difference, resistance to flow
A
F=∆P/R
flow = change in pressure / resistance
9
Q
Why does air move in and out of lungs
What does this have to do with Boyle’s law
A
P a/v is alternately less than and greater than atmospheric pressure
Boyles law is P1V1=P2V2
10
Q
Describe pressures in respiration:
Atmospheric
Alveolar
Intrapleural
Transpulmonary
Their importance to lung ventilation?
A
Ptp = P alv - P ip
If atm pressure is less than alv pressure, expiration
Opposite, inspiration
11
Q
Why is intrapleural pressure always subatmospheric under normal conditions
A
Lungs recoil in
Chest recoils out
12
Q
Primary muscles that control ventilation, their roles during inspiration and expiration
A
Inspiration:
External intercostal
Diaphragm
Expiration:
Internal intercostal
13
Q
Pressure and volume relationships in a respiratory cycle
A
Inspiration: P ip becomes subatmospheric P tp increases P alv becomes subatmospheric Lung volume increases
Expiration:
P alv becomes greater than P atm
Lung volume decreases
14
Q
What happens to P ip and P TP during a pneumothorax
A
Everything is the same
15
Q
Lung compliance?
Determinants of lung compliance
A
Compliance describes stretchability and is the inverse of stiffness (amount of force needed to ventilate lung)
Lung elasticity
Surface tension
16
Q
What does surfactant do?
Example of abnormal lung function due to deficiency of surfactant
A
Amphipathic phospholipid and protein molecule that forms monolayer between air and water. Reduces surface tension especially in small alveoli.
Deficiency causes respiratory distress. Lungs resist expansion. 2nd leading cause of death in premature infants.
17
Q
5 Factors that determine airway resistance
A
Tube radius
R=∆P/flow
Transpulmonary pressure (dilates bronchioles)
Elasticity of tissue
Neural and chemical control of smooth muscles
18
Q
Breathing pattern of people with severe airway obstruction?
Reason?
A
Deeper breathing
Increase ∆P
19
Q
Diseases that involve abnormal airway resistance
Principle of Heimlich maneuver
A
Asthma
COPD
Emphysema
Chronic bronchitis
Heimlich dislodges things in upper respiratory tract
20
Q
Various lung volumes and capacities
Typical values
A
Tidal volume - 500 ml
Inspiratory reserve - 3000 ml
Expiratory res. - 1500 ml
Residual vol. - 1000 ml
Vital capacity = IRV, ERV, TV2
Total capacity = vital capacity + residual vol.
21
Q
Minute ventilation:
Typical value?
A
Ml/min = tidal Vol. x respiratory rate
= 500 ml x 10 breaths = 5000 ml/min
22
Q
Types of dead space
Volume for anatomical dead space
A
Anatomical dead space = ~ 150 ml
Alveolar dead space - when mismatch b/t ventilation and blood flow
Physiologic dead space = anatomical + alveolar
23
Q
Minute ventilation vs. alveolar ventilation
A
Alveolar = (tidal vol. - dead space) x respiratory rate
-takes into account dead space
24
Q
Dalton’s law:
Partial pressure of gas:
A
Dalton: total pressure = sum of individual pressures (partial pressures)
25
Henry’s law
Factors that determine the concentration of a gas in a liquid
Henry: amount of gas dissolved in a liquid is proportional to the partial pressure of that gas in equilibrium with the liquid
Gases in a liquid diffuse from higher partial pressure to lower partial pressure
Concentration of gas in liquid: determined by which gas, partial pressure, temp.
26
Typical values for partial pressures of O2 and CO2 in
Atmosphere:
Alveolar air:
End of pulmonary capillary:
Systemic capillaries:
Beginning of a pulmonary capillary:
```
Atmosphere: O=160, CO2=.3
Alveolar air: O=105, CO2=40
End of pulm cap: O=40, CO2= 46
Systemic capillaries: O<40, CO2<46
Beginning pulm cap: O=100, CO2=40
```
27
Factors that affect alveolar gas pressures
Atmospheric P
Rate of alveolar ventilation
Rate of O2 consumption
28
Hypoventilation
Hyperventilation
Effects on alveolar gas pressures
Hypo- ventilation decreased rel to metabolism
Decrease alv O, inc. CO2
Hyper-ventilation increased rel to metabolism
Increase alv O, dec. CO2
29
Effect of high altitude on partial pressure of oxygen in alveoli
Less PO2 at high altitude
30
Describe gas exchange across the alveolar capillary membrane
Complete equilibration occurs at the end of a pulmonary capillary
Gases move with their pressure gradient
31
Ventilation-perfusion inequality:
Factors that can cause one
Lower blood PO2
Disease can make it worse
Vasc. Space with no ventilation
Ventilated space with no blood supply
Smooth muscle responses minimize through vasoconstriction or bronchoconstriction
32
How do these affect gas exchange:
Partial pressure gradient
Membrane area
Membrane thickness
PPG: gases go from high to low
Membrane area: more area more exchange
Thickness: thicker, harder to cross
33
External vs. internal respiration
External: air and blood in pulm caps
Internal: blood and systemic caps and cells
34
Forms of oxygen transport in blood
Importance of each
Amount of oxygen carried on each
Dissolved in blood - less than 10% what is needed for base metabolism
Hemoglobin - carries 98% of total O2 in blood
Max O2 per molecule of Hb is 4
35
Oxygen hemoglobin dissociation curve:
Relationship b/t PO2 and % saturation of Hb with O2
Significance of shape of this relationship?
Grows exponentially b/t 20 and 40 mmHg PO2
36
Oxygen hemoglobin dissociation curve:
How DPG, temp and H+ affect affinity of O2 for Hb and physiological importance of these effects
DPG reduces Hb binding of O2
Low temps = better hemoglobin saturation
Low acid = higher saturation
37
Oxygen hemoglobin dissociation curve:
Differences among O2 content of blood, PO2 and Hb saturation
PO2 is dissolved O2
| O2 bound to Hb can't diffuse
38
Oxygen hemoglobin dissociation curve:
Effects of anemia and CO on O2 content of blood and % Hb saturation with O2
Anemia - less Hb, doesn't change arterial PO2 or Hb saturation, just overall less O2 because less Hb
CO - replaces O2 on Hb, Hb 200x higher affinity for CO than O2
39
Three forms of CO2 that are transported in blood
Dissolved (7%)
Bound to Hb (23%)
HCO3 (70%)
40
Role of carbonic anhydrase
Forms carbonic acid from CO2 and H2O
41
How is H+ transported in the blood
Binds to his residues on Hb, affinity depends on PO2. OxyHb low affinity for H+
42
Respiratory acidosis:
Respiratory alkalosis:
How do these relate to hypo and hyperventilation
Acidosis: RR lower than normal or hypoventilation, increased PCO2 and [H+]
Alkalosis: RR faster than normal or hyperventilation, decreased H+ and PCO2
43
Less than _ o oxygen in blood is dissolved
2%
44
We rely on O2 bound to hemoglobin to carry ~_ % of total O2 in blood
98%
45
Systemic venous PO2
Systemic arterial PO2
40
| 100
46
T/F only dissolved O2 can diffuse into tissues
True
47
What happens to O2 bound to Hb when PO2 falls
O2 is released
48
Role of medulla oblongata in respiration
Determining the basic pattern of respiratory activity
49
How are medullary inspiratory neurons pacemakers?
They respond to receptors and drugs and control muscles that cause inspiration
50
Role of pulmonary stretch receptors in control of respiration
Modulate pacemaker neurons
51
Locations and functions of peripheral and central chemoreceptorss
Peripheral: stimulated by high H+ or low PO2
Central: stimulated. By high H+ in brain
Modulate ventilation
52
Factors that can modify the basic breathing pattern
PO2 down
PCO2 up
H+ up
Drugs
53
Respiratory consequences of changing PO2, PCO2, pH
Low PO2, inc. RR
High PCO2, inc. RR
Low pH, Inc. RR
54
Metabolic vs respiratory acidosis
Metabolic vs respiratory alkalosis
Acidosis:
- metabolic = excess lactic acid
- Respiratory = excess carbonic acid
Alkalosis:
- metabolic = severe vomiting
- respiratory = RR will slow
55
Effects of exercise on minute ventilation and arterial PO2, PCO2, H+
Increase minute ventilation
Arterial PO2 and PCO2 don't change
Intense exercise increases [H+]
56
Factors that stimulate ventilation during exercise
Temperature
Proprioceptors
Epinephrine and K+
Conditioned responses
57
Hypoxia:
Deficiency of O2 in tissues
58
Categories of hypoxia
4 causes of hypoxemia
Hypoxemia (hypoxic hypoxia)
Anemic hypoxia
Ischemic hypoxia
Histotoxic hypoxia
1. Hypoventilation
2. Diffusion impairment (thick alveoli/blood interface)
3. Vascular shunt (blood bypasses alveoli)
4. Ventilation-perfusion inequality (consequence of COPD)
59
Physiological responses that occur with acclimatization over a period of days at high altitude
```
Increased ventilation
Increased anaerobic glycolysis
Increased erythropoiesis
Increased DPG
Increased components to deliver O2
```
60
Principles behind various methods used to increase athletic performance by increasing oxygen carrying capacity of the blood
Live high train low (vice versa)
RBC packing
Gene therapy to increase EPO
Basically want to increase EPO
61
How many muscles involved in speech
100
62
Pediatric voice disorder frequency
6 to 23%
63
Pathology of pediatric dysphonia
```
Disease
Vocal nodules
Vocal cysts
Vocal paralysis
Laryngeal webs
Vocal fold dysfunction
```
64
Most common cause of pediatric dysphonia
Vocal nodules
65
Speech sound disorders
```
Developmental
Phonological
Placement/phonetic
Compensatory
Secondary to obligatory causes
```
66
T/F oral motor therapy is evidence based
FALSE
67
Dysarthria
Collective name for group of neurologic speech disorders resulting from abnormalities in control of different aspects of speech
68
Two kinds of dysarthria in Cerebral palsy kids, differences b/t the two
Athetoid - slow rate, dysrhythmia, stoppages, reduced stress
Spastic - breathy voice, monopitch/loudness, nasal,
69
T/F most kids present with a pure dysarthria
FALSE
70
Childhood apraxia of speech:
Neuromuscular deficits?
Neurological childhood speech sound disorder, precision and consistency are impaired.
Absence of neuromuscular deficits.
71
What does the velopharyngeal mechanism do
Alters general shape and resonant characteristics of vocal tract
Connects/disconnects the oral and nasal cavities
72
What is the most important muscle for providing adequate velopharyngeal closure for speech
Levator veli palatini
73
Things that can cause a VP insufficiency
```
Short soft palate
Adenoidectomy
Palatopharyngeal disproportion
Palatal resection from cancer
Trauma to palate
```
74
Alveolar bone grafting is done when
5-9 years
75
T/F speech therapy reduces hypernasality
FALSE
76
_ is the treatment of choice for children with VPD
Surgery
77
Functions of saliva (4)
Taste
Lubricant
Starts digestion of starch
Starts digestion of fat
78
Parotid duct:
Submandibular duct:
Sublingual duct:
Parotid = stensen’s
Submandibular = wharton’s
Sublingual = rivinus
79
Minor glands are mostly _ except _
Mucous except von ebner’s
80
Von ebner’s glands facilitate _
Taste
81
Von ebners glands secrete _ that helps with _ digestion
Lingual lipase
| Fatty acid
82
saliva is made of:
```
Water - 99.5%
Inorganic salts - Na, K, Cl, bicarbonate, CaPO3, MgSO4
Organic Components
-Acinar cellular origin
-Nonacinar origin
```
83
Difference b/t acinar and non-acinar origin of organic components
Acinar = amylase, lipase, mucoproteins, proline rich proteins, tyrosine rich proteins
Non-acinar = lysozyme, Ig, growth factors, regulatory peptides
84
What happens when salivary fluid secretion is stimulated
Ca opens the Cl and K channels
| Na leaks through tight junctions to follow Cl
85
_ happens in acini because it is H2O _
| _ happens in duct because it is H2O _
Secretion in acini, H2O permeable
Reabsorption in duct, H2O impermeable
86
Most abundant protein in saliva
Mucin
87
Mucin is made by _ and _
Amylase is made by _
Mucin - sublingual and submandibular
Amylase - parotid
88
3 immune proteins in saliva
Muramidase
Ig
Lactoferrin
89
Autonomics innervate what 4 cells to control salivation
Acinar cells
Ductal cells
Blood vessels
Myoepithelial cells
90
Parasympathetic and sympathetic NTM involved in salivation
```
P = ACh
S = NE
```
91
Saliva flow stimulation steps
1. Muscarinic or a-adrenergic receptor activation
2. Intracellular Ca
3. Ca activated K and Cl channels
4. Increase luminal Cl concentration
5. Intercellular Na follows
6. Water follows NaCl
92
NE stimulates _ saliva
Protein rich
93
Xerostomia is caused by 2 drugs
Anti-cholinergic
| Radiation
94
AI disorder that causes xerostomia
Sjorgren’s syndrome
95
The change from absorption to secretion happens in the _
Small intestine
96
T/F GI tissue has the same structure from upper esophagus all the way down
FALSE, mid esophagus
97
Sucrose is made of _
| Maltose is made of _
Glucose-fructose
| Glucose-glucose
98
_ are essential for digestion and absorption of carbs
Brush border ectoenzymes
99
Glucose and galactose are transported into membrane cells with _ by the enzyme _
Fructose is brought in by _
All 3 are moved to blood by enzyme _
Na by SGLT1
GLUT5
GLUT2
100
Proteins are broken into peptides in _
Stomach
| Small Int.
101
Proteins are broken down to peptides in the SI by _
Trypsinogen
Cymotrypsinogen
Procarboxypeptidase A/B
Proelastase
102
_ is an essential protease for cleavage of proteins
Trypsin
103
_ cleaves trypsinogen to form trypsin
Enteropeptidase
104
AAs are transported by _ or _
Na dependent
Or
Na independent transporters
105
All proteases are released as _
Proenzymes
106
T/F luminal peptidases are sufficient to break down protein
FALSE
| Brush border enzymes are also needed
107
3 sources of lipase
Lingual lipase
Gastric lipase
Pancreatic lipase
108
FA absorption occurs in the _, but digestion occurs in the _
SI (duodenum)
| Stomach and duodenum
109
T/F lipases are water soluble
True
110
How does lipase interact with fat
Colipase
111
What 2 things emulsify fats
Bile salt
| Phospholipid
112
How do micelles enhance absorption of FAs
They are in equilibrium with free FA
They are constantly breaking down and reforming
113
T/F free fatty acids and mono glycerine seems are found in systemic circulation
FALSE - triglycerides are though
114
4 fat soluble vitamins
ADEK
115
All water soluble vitamins except _ are absorbed by active transport
B12
116
Absorption of Na occurs _
Throughout entire GI tract
117
T/F absorption of Fe is very efficient
FALSE
118
Minerals are absorbed where
All segments of intestine
119
3 things that regulate GI functions
Neurons (Autonomic, enteric)
Paracrine
Endocrine
120
4 plexuses of the enteric nervous system
Myenteric
Deep muscular
Submucosal
Mucosal
121
3 types of neurons in the ENS
What do they do
Motor - muscle and gland func.
Inter - interac. B/t layers of GI
Sensory
122
What are GI reflex arcs?
| How stimulated?
Mechano/osmo/chemo receptors sense
Distention of wall
Chyme osmolarity
Chyme acidity
Chyme concentrations
Send smooth muscle or gland response to GI lumen
123
4 main GI hormones
Gastric
Cholecystokinin
Secretion
Glucose-dependent insulinotropic peptide
124
3 general features of GI hormones
Feedback control system to regulate GI lumen
Affect more than 1 type of target cell
Have synergistic effects
125
3 phases of GI control, defined
Cephalic - PS nerve fibers affect ENS
Gastric - short/long neural reflexes and gastrin
Intestinal - short/long neural reflexes, secretin, CCK, GIP
126
3 sections of the stomach
| 2 glandular regions
Fundus, body, antrum
Oxyntic glandular region
Pyloric granular region
127
3 digestive secretions of gastric cells, which cells secrete which
HCl - parietal cells
Intrinsic factor - parietal
Pepsinogen - chief cells
128
_ regulate stomach acid secretion
Inputs to parietal cells
129
_ is the strongest HCl stimulant, and its release can be triggered by _
Histamine
| Gastrin or ACh
130
_ inhibits release of HCl
Somatostatin
131
Pepsinogen is a _, which means _
Zymogen
| It needs to be cleaved to become active
132
Enterogastrones do what?
| Two examples of enterogastrones
Inhibit secretion Or motility in stomach
Secretion and CCK
133
Pancreas is a _ gland, and releases
Exocrine
Bicarbonate ions
Digestive enzymes
Trypsinogen
134
_ converts trypsinogen to trypsin
Enteropeptidase
135
Bicarbonate secretion is just _ in reverse
HCl
136
What two things regulate bicarbonate secretion in pancreas
Hormone regulation by secretin
Feedback regulation by acidity
137
What does the liver do in digestion
Produces and secretes bile
138
The liver makes _ and secretes _ bile salts/day
20-60 mg
1,200-3,600 mg
139
Bile salts are recycled through the _
Enterohepatic circulation
140
Peristalsis vs. segmentation
During absorption, _ contractions occur, after most absorption is done, _ contractions occur
P: progressive contractions of successive sections
S: closely spaced contractions of circular muscle
Segmentation, peristalsis
141
Peristalsis is driven by _
A migrating myoelectric complex
142
Primary purpose of large intestine
Transport Na from lumen to blood
143
Large intestine has _ contractions
Both segmentation (continuous, slow) and peristalsis (3-4 x/day)
144
How does the kidney regulate body fluid composition (4 things)
Endocrine functions?
Regulates water and salt balance (Na, K, Ca)
Balances intake with excretion
Removes waste, drugs and foreign chemicals
Gluconeogenesis
EP/Renin/1,25-DHVD
145
How is renal failure associated with paths of the oral cavity
What are some manifestations of the condition
What dental practices are contraindicated in patients with renal insufficiency
ESRD pts have high pH in mouth causing them to have:
- ammonia breath
- Gingival enlargement
- xerostomia
- tooth problems (loss, narrowing pulp, necrosis)
CXs
- nephrotoxic drugs (tetracycline, acyclovir, aspirin, NSAIDs)
- anything that will make them bleed
146
Basic structure of kidney
Organization of nephron (components and path of fluid)
Retroperitoneal
Cortex/medulla
```
Nephron -
Cluster of capillaries
Long hollow tube (1 cell layer thick)
Corpuscle (glomerulus + capsule)
PCT
loop of henle
DCT
Collecting duct (shared)
```
147
In renal processes,
Filtration:
Absorption:
Secretion:
Molecules in each process, where in the nephron does it occur
F: solutes/water from blood to tubular fluid in Bowman’s space
S: substances from blood in peritubular caps into tubular fluid
A: substances from tubular fluid to blood in peritubular caps
148
Renal clearance:
How does it relate to kidney function
The rate of excretion of a solute through kidney. Volume of plasma from which all of a substance is removed to urine.
Important in monitoring renal function
149
How is glomerular filtration rate regulated?
Smooth muscle contraction in afferent/efferent arterioles
JGA response (renin)
Symp NS
150
Two intrinsic mechanisms involved with the phenomenon of auto regulation
What else maintains GFR
1. Myogenic mechanism - vasc. Smooth muscle contracts when stretched, relax if not
2. Tubuloglomerular feedback - feedback from JGA adjusts afferent arteriole diameter and GFR
Other factors/extrinsic mechanisms
151
General principles of molecular transport across and around cells, including:
Energy requirements
Solvent drag
Distinction b/t symporters and antiporters
Facilitated diffusion requires specific membrane protein
Solvent drag results from solutes being carried by water in paracellular transport
152
How is Na transported into or out of
Proximal tubule:
Loop of henle:
Distal tubule/collecting duct:
Proximal tubule:
Glucose and AA’s reabosrbed with Na using symporters
With bicarbonate reabsorption using Na/H antiporter
Loop:
(Thick) - Na K 2Cl symporter
Distal tubule:
Na/Cl symptorter
Sodium channels to absorb Na and secrete K
153
Major Na transporters and where they are found in a nephron
S
154
Different Na/water permeabilities of each nephron segment
Prox tubule: 67% NaCl and water reabsorbed
Loop of henle: 25% NaCl, 15 % water
Distal tubule: 8% NaCl, water variable
155
What does it mean to produce concentrated urine
Which parts of the nephron are essential to this process
Concentrated urine is high conc or solutes / kg H2O
ADH increases permeability of late Distal Tubule and collecting duct to water (increases aquaporins)
If water reabsorbed, more concentrated urine (high ADH)
156
How does neural and hormonal regulation of Na and water transport along the nephron balance water and Na secretion to maintain total body volume?
Renin converts angiotensinogen to angiotensin I
ACE converts AT I to AT II
AT II causes vasoconstriction, stimulates release of ADH, increases sympathetic activity, stimulates aldosterone
Aldosterone increases NaCl reabsorption in distal tubule
157
How is K transport by the nephron regulated based on need
| To balance K intake and excretion
Secreted in distal tubule depending on ATPase
Intercalated cells reabsorb K when depleted
Increased K stimulates aldosterone release, increases K secretion
158
pH limits of body
6.8 to 7.8
159
Volatile vs. non-volatile vs. titratable acids
Volatile - can be exhaled or dissipated by lungs (CO2)
Non-volatile - from metabolism or diet, neutralized by HCO3-, regulated by renal sys.
Titratable - can be measured by titration with a base to a pH of 7.4
160
Where along the nephron is acid secreted and bicarbonate reabsorbed
What are the transport mechanisms
Prox tubule: 80% of filtered HCO3 is reabsorbed. CA makes HCO3 from CO2 + H2O
Thick ascending limb of loop: similar to prox
Late distal tubule and collecting duct: CA in intercalated cells makes H and HCO3
H secreted through ATPase
HCO3 is reabsorbed in late distal tubule and collecting duct
161
When and how does the kidney produce new bicarbonate through production of ammonium
After all HCO3 has been reabsorbed and HPO4 is depleted, kidney makes NH4 from glutamine
162
4 major classes of acid:base disorders
Cause and compensatory mechanism for each
Respiratory acidosis - CO2 build up
make new HCO3
Respiratory alkalosis - High pH due to low PCO2, hyperventilation
Excrete HCO3
Metabolic acidosis - low HCO3, diarrhea, renal failure
Hyperventilate, make new HCO3
Metabolic alkalosis - hi pH due to excess HCO3
Vomiting, antacids, hemorrhage
Hypoventilate, excrete HCO3
163
Ca containing compartments of the body
Proportion of Ca in each compartment
Intracellular fluid (1%)
ECF (0.1%)
Bone (99%)
164
Source and actions of the three hormones that regulate calcium homeostasis
Parathyroid hormone
- parathyroid gland
- increases bone resorption, renal reabsorption, stimulates calcitrol production
Calcitrol
- thyroid parafollicular cells
- stimulates active transport of Ca absorption in small intestine
- facilitates action of PTH, increases renal Ca transport
Calcitonin
- released in response to hypercalcemia
- increases bone deposition
165
Where along the nephron is calcium regulated
Transport mechanisms involved with its reabsorption/secretion
Proximal tubule - paracellular transport/solvent drag
Thick ascending - trans/paracellular transport (not solvent drag)
Distal - transcellular reabsorption of Ca
166
Why are diuretics necessary
Different classes
CHF - increased Na and H2O reabsorption
Hypertension
```
Osmotic diuretics
CA inhibitors
Loop diuretics
Thiazides
K+ sparing
Aquaretics
```
167
How does each class of diuretics gain access to nephron
Which segment of the nephron do they affect, what are their basic mechanism of action
Osmotic
- increases osmotic pressure in tubular fluid
- gain access to tubule by glomerular filtration
CA inhibitors
- reduce Na reabsorption by inhibiting CA, reducing H available for Na/H antiporter
- access proximal tubule via secretion
Loop
- inhibit Na reabsorption in ascending limb by inhibiting Na K 2CL symporter
- secreted into proximal tubule
Thiazide
- secreted into proximal tubule
- act in early distal tubule to block Na/Cl transporter
K sparing
- secreted into proximal tubule
- act where K is secreted into tubular fluid by principal cells
- block aldosterone increasing Na transporters
Aquaretics
-increase water excretion by blocking action of ADH in distal tubules and collecting duct
168
Major side effects of diuretics on K, HCO3, Ca excretion
Excretion of K
Metabolic acidosis
Ca excretion
169
What does hemodialysis do?
When is it necessary?
Removes waste products from blood
When kidney function has been impaired
170
How does the hemodialysis machine work?
How is patient blood accessed?
Possible side effects/complications?
Blood is removed and passed through dialyzer then filtered
Catheter, AV fistula, AV graft
Fatigue, chest pain, cramps, nausea, headaches, sepsis, endocarditis, osteomyelitis, amyloid deposits in joints
171
Function of EP/procrit
Where does it come from
What stimulates it
Effects on erythropoiesis
Stimulates bone marrow to make RBCs
Made by interstitial fibroblasts in renal cortex
Stimulated by low PO2
Increases erythropoiesis
172
Disorders/problems with too much or too little EP
Flu-like symptoms, headaches, high BP, cardiovascular problems
