Renal System Flashcards

1
Q

Primary Function–>

A

Maintain a stable internal environment for optimal cell and tissue metabolism.

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2
Q

Electrolyte homeostasis

A

Na+, K+, Ca2+, Cl-, HPO42-

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3
Q

Regulation of blood pH

A

Removes H+ from blood

maintains bicarbonate ions (HCO3-) in blood

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4
Q

Regulation of Blood Volume/Blood Pressure

A

Retention of water = increases BP

Elimination of water = decreases BP

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5
Q

Osmoregulation

A

at 300 mOsm/L

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6
Q

Hormones Produced by the Kidney

A

Calcitriol - form of Vitamin D calcium homeostasis
Erythropoietin - RBC production
Renin – Blood pressure regulation

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7
Q

Excretion of wastes

A

Ammonia & Urea (protein metabolism)
Bilirubin
Creatinine (waste product of creatine phosphate)
Uric Acid (purine metabolism – A’s & G’s of DNA)
Arthritis known as Gout excess uric acid
Drugs and toxins

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8
Q

Function 7. Performs________

A

gluconeogenesis: Synthesis of glucose from amino acids

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9
Q

Structure: Renal capsule

A

Tightly adhering capsule covers kidney

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10
Q

Structure:Adipose capsule

A

Fat capsule surrounds each kidney

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11
Q

Structure:Renal fascia

A

-Fibrous tissue attaches/suspends kidney to the posterior abdominal wall.

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12
Q

Structure:Hilum

A

Medial indentation where the renal blood vessels, nerves, lymphatic vessels, and ureter enter and exit the kidneys.

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13
Q

Structure:Renal cortex

A
  • Is the outer layer of each kidney.

- Contains all of the glomeruli, most of the proximal tubules, and some segments of the distal tubule.

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14
Q

Structure:Renal columns

A

-Extend from the cortex down between the renal pyramids.

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15
Q

Structure:Renal medulla

A
  • inner part of each kidney that contains tubules and the collecting duct.
  • Consists of regions called the pyramids.
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16
Q

Structure:Minor calyx

A
  • Receives urine from the collecting ducts through the renal papilla.
  • Apexes of the pyramids project into a cup-shaped cavity that join together to form a major calyx.
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17
Q

Structure:Major calyx

A

-Joins to form the renal pelvis.

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18
Q

Structure:Renal pelvis

A

-Joins the proximal end of the ureter

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19
Q

Parasagittal section through right Kidney

A

Posterior : protected by 11th and 12th rib; protected by adipose
Anterior: Adrenal gland/Transverse colon

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20
Q

Ureters:
Are _____ long.
Are long, intertwining ____ _______bundles.
Pass obliquely into the ____ ________of the ______
_____ ________ moves urine to the bladder.
________ compresses the_____ __________ to avoid _____ ____

A

Are 30 cm long.
Are long, intertwining smooth muscle bundles.
Pass obliquely into the posterior aspect of the bladder.
Peristaltic activity moves urine to the bladder.
Micturition compresses the lower end of the ureter to avoid urine reflux.

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21
Q

**Bladder 3 parts:

A

Detrusor muscle (wall)
Trigone
Transitional epithelium

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22
Q

*****Urethra:
Length in females/males
Which is sphincter is involuntary/voluntary
What kind of muscle in each?

A

Internal urethral sphincter - involuntary
Smooth muscle @ jct. of bladder & urethra
External urethral sphincter – voluntary
Striated skeletal muscle
Between 3 and 4 cm long in females
Between 18 and 20 cm long in males

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23
Q

**Micturition or urination (voiding):

A

• when volume exceeds 250-300 mL Stretch receptors signal spinal cord and brain

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24
Q

**Micturition center in sacral spinal cord triggers reflex:

A

• parasympathetic fibers cause detrusor muscle to contract – squeezes out urine
and
• Internal & external sphincter muscles to relax to allow flow

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25
Filling initiates a desire to urinate before the reflex actually occurs
* conscious control of external sphincter | * cerebral cortex can initiate micturition or delay it for a limited period of time
26
Bladder and Urethra reflex | what is required for micturition and what is it stimulated by? then what happens?
Reflex arc is required for micturition-->Is stimulated by mechanoreceptors from stretching-->Bladder fullness is sensed; impulses are sent to the sacral level of the spinal cord -->When the bladder accumulates 250 to 300 ml of urine, the bladder contracts and the internal urethral sphincter relaxes from activation of the spinal reflex arc (micturition reflex) -->At this time, the urge to void is felt-->In older children and adults, reflex can be inhibited or facilitated by impulses coming from brain or voluntary control of micturition
27
10. Vasa recta – Is a network of capillaries for the juxtamedullary nephrons. – Influences osmolar concentration of the medullary extracellular fluid, which is important for the formation of a concentrated urine. List renal arteries to vasa recta
1. Renal Arteries 2. Segmental Arteries 3. Interlobar arteries 4. Arcuate arteries 5. Interlobular arteries 6. Afferent arterioles 7. Glomerular capillaries 8. Efferent arterioles 9. Peritubular capillaries 10. Vasa recta
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***1. Renal arteries (role)
Supply blood to the kidneys.
29
****2. Segmental arteries
branches of the renal artery.
30
****3. Interlobar arteries
Travel between the pyramids.
31
***4. Arcuate arteries
Arch over the base of the pyramids
32
****5. Interlobular arteries.
- extend through the cortex toward the periphery of the kidneys and supply the afferent glomerular arteriole
33
****6. Afferent arterioles
– supply glomerular capillaries.
34
****7. Glomerular capillaries
- site of filtration
35
****8. Efferent arterioles
- Convey blood to a second capillary bed.
36
***9. Peritubular capillaries surround the ______ and _______and _______
- Surround the proximal and distal convoluted tubules and loop of Henle.
37
**10. Vasa recta
– Is a network of capillaries for the juxtamedullary nephrons. – Influences osmolar concentration of the medullary extracellular fluid, which is important for the formation of a concentrated urine.
38
*Kidneys are less
than 0.5% of total body mass, but receive 20-25% of | resting cardiac output
39
After peritubular capillaries
Interlobular veins--> Arcuate veins--> Interlobar veins-->Renal vein
40
Identify renal cortex and renal pyramid
renal cortex | Renal pyramid in renal medulla
41
_______per kidney – they are the functional unit of the kidney.
1.2 million
42
Superficial cortical nephrons:
Make up 85% of all nephrons, which extend | partially into the medulla.
43
Juxtamedullary nephrons
Lie close to and extend deep into the medulla | and are important for the process of concentrating urine; secrete renin.
44
Renal Physiology :Describe 3 major processes
Filtration from blood plasma into nephron Tubular reabsorption from fluid into blood Tubular secretion from blood into fluid
45
1. Glomerular filtration: substances)
Water & small solutes in blood plasma move across the wall of the glomerular capillaries into glomerular capsule and then renal tubules (PCT –> loop of Henle –> DCT –> Collecting duct)
46
2. Tubular reabsorption: as ____Move along____many solutes are ________= returned to _____
As “filtrate” moves along tubule water and many useful solutes reabsorbed = returned to blood
47
3. Tubular secretion:
“filtrate” moves along tubule other molecules (wastes, drugs, & excess ions) are secreted into fluid
48
Any solutes that remain in the fluid that drains into the renal pelvis
are excreted as urine
49
Excreted water (how much per day)
1-2 Liters per/ day
50
Distal convoluted tubule : _____ stimulate ______of ____
PTH stim.s reabsorption of Ca++
51
Intercalated cell
Regulation of pH via H+ andHCO3-
52
Principal cell
ADH and Aldosterone
53
Brush border villi
for reabsorption | Proximal convoluted tubule
54
H2O reabsorption
Thin descending limb of loop of Henle
55
Na+ K+ Cl- reabsorption
Thick descending limb of loop of Henle
56
Glomerulus within Bowman's capsule
Function : Filtration
57
Proximal tubule , Function | Tonicity of fluid?
Reabsorption of Na+, K+, Amino acids, bicarbonate, phosphate, urea, H2O Secretion of H+ foreign substances -Isotonic
58
Loop of henle, Function | Tonicity of fluid?
- Concentration of urine (countercurrent mechanism) - Descending loop water reabsorption (Na+ diffuses in) - Ascending loop Na+ Reabsorption ( active transport, water stays in) - Urea secretion in thin segment - Isotonic,hypertonic, hypotonic.
59
Distal tube , Function | Tonicity of fluid?
Reabsorption of Na+, H2O(ADH required) and HCO3- Secretion of K+ , urea, H+, NH3+,some drugs. -isotonic or hypotonic
60
Collecting duct, Function | Tonicity of fluid?
Reabsorption of H2O(ADH required) Reabsorption or secretion of Na+,K+, H+, NH3+ Urea reabsorption in the medulla - Final concentration
61
Tubular reabsorption: How many L of filtrate produced? what happens to that filtrate? Nephron must absorbed? _____% and as a result ______L of urine per day Water and _____move ______to ______ ______
180 (152) Liters/day of filtrate produced – obviously most of this needs to return Nephron must reabsorb 99% of the filtrate (as a result: 1-2 Liters of urine per day) Water + Solutes move “Tubules to Peritubular capillaries"
62
Tubular Reabsorption along the nephron 1.PCT with microvilli does most of the __________ Solutes reabsorbed by both ______and ________ ______,_______, _____ and ions (__,___,___,___,____) ____% of water follows by _______
1. PCT with microvilli does most of the reabsorption (remainder of nephron fine-tunes) – Solutes are reabsorbed by both active transport and passive diffusion Glucose, amino acids, urea and ions (Na+, K+, Ca2+, Cl-, bicarbonate, phosphate) – 65% of water follows by osmosis
63
* **Tubular Reabsorption along the nephron: | 1. PCT Transporters reabsorb water and solutes
**** 100% of Glucose, amino acids, lactic acid, water-soluble vitamins, and other nutrients are reabsorbed in the first half of the PCT **
64
PCT: Reabsorption of Na+ produces an
electrical gradient that caused Cl- to follow by passive | transport
65
PCT:Accumulation of NaCl outside of tubule
produces an osmotic gradient: Helps “pull” water out of tubule
66
2. Descending Limb of Loop of Henle: % of water filtered there? Movement of water? Comment on permeability of solutes
– 15% of the filtered water is reabsorbed in the descending limb – High solute content of the medulla “pulls” water out – Low permeability to solutes = little reabsorption of solutes
67
3. Ascending Limb of Loop of Henle: ______reclaim more ____ ____ ___and others by _____ 2 parts: _____and ______ which one is permeable to solute and almost impermeable to water? Which portion is HIGHLY permeable to ___ ___ ___and significant LESS permeable to water and _______
Variety of transporters reclaim more Na +, Cl-, and K + ions and other ions by diffusion – Thin, ascending segment: Is more permeable to solutes and almost impermeable to water. – Thick portion of the ascending segment: Is highly permeable to sodium, potassium, and chloride and significantly less permeable to water and urea.
68
4. DCT: What percentage of water absorbed there? What continues there DCT serves as what (IMPORTANT)
– Moderately permeable to solutes but absorbs about 15% of water - reabsorption of Na+ and Cl continues * ******The DCT serves as the major site where parathyroid hormone stimulates reabsorption of Ca+2
69
* *By end of DCT, what happens? | 5. Collecting duct contains ________ and _________cells, and what do they make?
* **95 % of solutes and water have been reabsorbed ** - Principal and Intercalated - final adjustments
70
***Principal cells:
****• Targeted by 2 hormones that promote reabsorption of more water and ions 1. ADH: increases water reabsorption (retention) 2. Aldosterone @ collecting duct: increases reabsorption of Na+ and Cl- Therefore water will also be reabsorbed! Secretion of K+ (adjust for dietary intake of K+)
71
*****Intercalated cells:
****help regulate pH of body fluids • Proton pumps (H+ATPases)secrete protons(H+) into tubule • Reabsorb bicarbonate ions(buffers blood pH)
72
``` Tubular secretion: Transfer of material from ____ Occurs where? ______ions to maintain ____ To eliminate excess _____ Drugs such as _______ ```
– Transfer of materials from blood into filtrate/urine – Occurs at various locations along the tubule – Hydrogen ions (H+) = to maintain pH – To eliminate excess K+, ammonia, urea, creatinine – Drugs such as penicillin
73
Major Hormone: Angiotensin II Major Stiumuli that trigger releases? Mechanism and site of action? Effects
- low blood volume or low blood pressure stimulates renin-induced production of angiotensin II - Stimulate activity of Na+/H+ antiporters in proximal tubules cells - Increases reabsorption of Na+, other solutes, and water which increases blood volume
74
Major Hormone: Aldosterone Major Stimuli that trigger releases? is released from where? Mechanism and site of action? Effects
- Increased angiotensin II level and increased level of plasma K+ promote release of aldosterone by adrenal cortex - Enhances activity of sodium potassium pumps in basolateral membrane of principal cells in collecting duct - Increased secretion of K+ and Reabsorption of Na+ , Cl-increases reabsorption of water, which increases blood volume
75
Normal GFR
120ml/min
76
Major Hormone: ADH / Vasopressin Major Stiumuli that trigger releases? Mechanism and site of action? Effects
- Increased osmolarity of extracellular fluid or decreased blood volume promotes release of ADH from the posterior pituitary gland -Stimulates insertion of water channel proteins(Aquaporin-2) into the apical membrane of principal cells COLLECTING DUCT Effects: Increase falcultative reabsorption of water, which thus decreases blood volume
77
Angiotensin II increased effect in ______greater than ______arterioles and it effect on GFR?
efferent> afferent and increase GFR
78
Major Hormone:Atrial natriuetric peptide Major Stimuli that trigger releases? Mechanism and site of action? Effects
Strigger:Stretching of atrial of heart stimulates secretion of ANP MOA: suppresses reabsorption of Na+ and water in proximal tubule and collecting duct Also inhibits secretion of aldosterone and ADH Effects: Increases excretion of Na+ in urine (Natriuresis) ; Increases urine output (diuresis); and thus decreases blood volume
79
Major Hormone:Parathyroid Hormone Major Stimuli that trigger releases? Mechanism and site of action? Effects
Strigger: Decreased level of plasma Ca+ promotes release of PTH from parathyroid gland MOA: stimulates the opening of Ca2+ channels in apical membranes of early distal tubule cells Effects: Increases reabsorption of Ca2+
80
Blood pressure drives_________ • Approximately ______% of renal plasma flow becomes filtrate • average adult male rate is _____ml/min and female is_____ml/min • ________ in males; _______ in females
Filtration; 20% 125 ml/min ; 105 ml/min 180 Liters/day 150 Liters/day
81
Parts of the Renal Corpuscle
``` Glomerulus Bowman’s (glomerular) capsule Mesangial cells Glomerular endothelial cells Visceral epithelium of the Bowman capsule ```
82
Glomerulus part of the ________and is a _______supplied by the _______ arteriole and is______by the _________ arteriole
Glomerulus - Set of fenestrated capillaries | • Supplied by the afferent arteriole and drained by the efferent arteriole
83
Bowman’s (glomerular) capsule is a
• Circular space between visceral and parietal epithelium
84
Mesangial cells: Supports the ______ and respond to _______ to regulate what?
support the glomerular capillaries and respond to ANP to regulate glomerular capillary flow.
85
Glomerular endothelial cells | Synthesize (2)
Glomerular endothelial cells • Synthesize nitric oxide (a vasodilator). • Synthesize endothelin-1 (a vasocon
86
Visceral epithelium of the Bowman capsule Composed of cells called _______ are _______ Form an Elaborate network of ________ called_________ and does what ?
Visceral epithelium of the Bowman capsule • Is composed of cells called podocytes. o Are footlike processes. o Form an elaborate network of intercellular clefts called filtration slits; modulate filtration
87
Glomerular filtration membrane: what moves through the membrane and become primary urine or ____ Can blood cells enter or be filtered? What retard filtration of anionic proteins? what does it prevent?
- Water, Ions, small molecules & small proteins move through the membrane and become “primary urine” or “filtrate”. - Blood cells, large/medium sized proteins cannot normally be filtered - Negativity of the filtration membrane retard filtration of anionic proteins (prevents proteinuria)
88
****JUXTAGLOMERULAR APPARATUS: Control of what occurs at this site?
Control of renal blood flow (RBF), glomerular filtration, and renin secretion occurs at this site.
89
****Juxtaglomerular cells: located where?
These specialized cells are located around the afferent arteriole where the afferent arteriole enters the glomerulus.
90
****Mesangial cells: are _____ _____that _______ and help regulate________and _______ ______From ______
specialized contractile cells that support glomerulus and help regulate glomerular blood flow; and remove macromolecules from filtration
91
****Macula densa is the portion of _____ ____Tubule which contains what? located where? FUNCTION (main) detect what?
o Portion of the distal convoluted tubule with specialized sodium and chloride sensing cells is located between the afferent and efferent arterioles. *****Detect high filtrate rate in the DCT which results in a decrease of nitric oxide and vasoconstriction in the afferent arterioles.
92
Blood flow through kidney from Abdominal Aorta to Inferior Vena Cava? 13 steps ARSI-AGEPI- AIRI
1. Abdominal Aorta 2. Renal Arteries 3. Segmental Arteries 4. Interlobar Arteries 5. Afferent Arterioles 6. Glomerular Capillaries 7. Efferent Arterioles 8. Peritubular Capillaries 9. InterLOBULAR Veins 10. Arcuate veins 11. Interlobar Vein 12. Renal Veins 13. Inferior Vena Cava
93
Review part of the Juxtaglomerular Apparatus
``` A – Renal corpuscle B – Proximal tubule C – Distal convoluted tubule D – Juxtaglomerular apparatus 2. Bowman's capsule – parietal layer 3. Bowman's capsule – visceral layer 4. Bowman's space (urinary space) 5a. Mesangium – Intraglomerular cell 5b. Mesangium – Extraglomerular cell 6. Granular cells (Juxtaglomerular cells) 7. Macula densa 9. Afferent arteriole 10. Glomerulus Capillaries 11. Efferent arteriole ```
94
Renal Blood flow Kidneys receive _____to _____ ml/min of blood;________ of CO). • _____-_____ml as plasma (renal plasma flow [RPF])
1000 to 1200; (20-25% of CO). | 600 to 700
95
GFR is regulated by 3 mechanisms:
– autoregulatory – neural – hormonal
96
Glomerular filtration rate (GFR) • 20% of the RPF (120 to 140 ml/min) is filtered into_______ GFR is Directly related to____________ in the _________ • If mean arterial pressure decreases or vascular resistance increases, then the RBF_______
- Bowman’s space - the perfusion pressure in the glomerular capillaries - decreases.
97
• FF = Filtration Fraction FF = GFR/RPF
FF= GFR/RPF
98
GFR regulation : Autoregulation Myogenic mechanism • If arterial pressure increases, stretch of the afferent arterioles__________ smooth muscle________ to_______ ______arteriole and perfusion
(pressure/stretch); increases, contracts; constrict afferent; decreases.
99
GFR regulation : Autoregulation Myogenic mechanism • If arterial pressure declines stretch of the ______arterioles __________, smooth muscle ________ to dilate _____ ______and perfusion_________
afferent arterioles decreases ; relaxes; afferent arteriole; increases.
100
TUBULOGLOMERULAR feedback (sodium chloride content) a.If sodium filtration increases, what happens to GFR? ________ _____cells stiumlates ______arteriolar ______ b. If sodium filtration decreases, what happens to GFR?
• If sodium filtration increases, GFR decreases. – Macula densa cells stimulate afferent arteriolar vasoconstriction. • If sodium filtration decreases, the opposite occurs—GFR increases.
101
2 parts of autoregulation:
Myogenic Mechanism | Tubuloglomerular Feedback
102
Second type of GFR is Neural Regulation 3 aspects
Sympathetic Nervous System Exercise and change in body position Severe hypoxia
103
Second type of GFR Neural Regulation aspects 1: SNS Sympathetic stimulation leads to what? which _______GFR Inhibition of sympathetic stimulation causes _______which _______GFR?
Sympathetic stimulation of afferent arterioles via alpha-1 (α-1) receptors causes vasoconstriction (decreases GFR). • Inhibition of Sympathetic nerves causes vasodilation (increases GFR).
104
***Second type of GFR Neural Regulation aspects 2:
• Activate renal sympathetic neurons, causes mild vasoconstriction.
105
***Second type of GFR Neural Regulation aspects 3:
Severe hypoxia: Stimulation of chemoreceptors | • Decreases RBF by means of sympathetic stimulation
106
****Third Type of GFR is Hormonal Regulation RAAS and Renin Which arteriole does angiotensin have greater effect?
Renin-angiotensin-aldosterone system (RAAS) • Increases systemic arterial pressure, and increases sodium reabsorption. Renin: Enzyme is formed and stored in afferent arterioles of the juxtaglomerular apparatus. • ****Renin helps form angiotensin I (physiologically inactive). • In the presence of angiotensin-converting enzyme (ACE), angiotensin I is converted to angiotensin II. • Angiotensin II – Stimulates the secretion of aldosterone by the adrenal cortex. – Is a potent vasoconstrictor. (constricts both afferent & efferent arterioles in kidney; with greater affect on efferent arteriole) – Stimulates antidiuretic hormone (ADH) secretion and thirst.
107
Tubuloglomerular feedback
Hypovolemia-->Hypotension--> Decrease Na+ at macular densa cells of distal tubules-->Renin release from Juxtaglomerular cells
108
****Natriuretic peptides | 2 types; where are they secreted
a. Atrial natriuretic peptide (ANP) is secreted from myocardial cells in the atria. b. Brain natriuretic peptide (BNP) is secreted from myocardial cells in the ventricles.
109
ANP and BNP 4 functin a) Inhibit _____and ______ _____by the kidney tubules b) Inhibit secretion of ____and ______ c) Vasodilate the ______arterioles and constrict the _____arterioles d) Increase UO, leading to decrease in ______ and ______, promote _____And _____loss
a) - Inhibit sodium and water reabsorption by kidney tubules. b) Inhibit secretion of renin and aldosterone. c) Vasodilate the afferent arterioles; constrict the efferent arterioles. d) Increase urine output, leading to decreased blood volume and blood pressure; promote sodium and water loss.
110
Regulatory Mechanisms of Glomerular Filtration Rate (GFR) Myogenic Mechanism Major stimulus ? Increased ________of _______ ____in_______arteriole walls due to __________ in______ Mechanism or site of action? those muscle _____, thereby _______ the lumen of _______ Effect on GFR?
MS: Increased stretching of smooth muscle fibers in afferent arteriole walls due to increase in BP Mechanism site of action: Stretch smooth muscle fibers contract , thereby narrowing the lumen of the afferent arterioles Effect on GFR: Decrease
111
Regulatory Mechanisms of Glomerular Filtration Rate Tubuloglomerular feedback Major stimulus ? Mechanism or site of action? Effect on GFR?
Major stimulus: Rapid delivery of Na+and Cl- to the macula densa due to high systemic BP MOA: Decrease the release of NO by the juxtaglomerular apparatus cause constriction of afferent arterioles Effect on GFR: Decrease
112
Regulatory Mechanisms of Glomerular Filtration Rate NEURAL REGULATION Major stimulus ? Mechanism or site of action? Effect on GFR?
Major Stimulus:Increase in level of activity of renal sympathetic nerves release norepinephrine MOA: Constriction of afferent arteriole through activation of alpha 1 receptors and increased release of renin Effect on GFR: Decrease
113
Regulatory Mechanisms of Glomerular Filtration Rate HORMONAL REGULATION: Angiotensin II Major stimulus ? Mechanism or site of action? Effect on GFR?
Major stimulus -->Angiotensin II: Decrease Blood volume and BP stimulates production of angiotensin II MOA: Constriction of both afferent and efferent arterioles Effect on GFR: Increase
114
Regulatory Mechanisms of Glomerular Filtration Rate HORMONAL REGULATION: ATRIAL NATRIURETIC Major stimulus ? Mechanism or site of action? Effect on GFR?
Major stimulus-->Stretching of the atria of the heart stimulates secretion of ANP MOA: Relaxation of mesangial cells in glomerulus increases capillary surface area available in filtration. Effect on GFR: Increase
115
Characteristics of Normal Urine: Volume
1-2 Liters in 24 hours(day)
116
Characteristics of Normal Urine: COLOR/ ODOR/specific gravity
concentrated urine is darker Urine of diabetic has a fruity odor due to ketone bodies pH between 4.6-8 average 6 1.001 to 1.035, the higher the concentration of solutes, THE HIGHER THE SPECIFIC GRAVITY
117
Summary of abnormal urine constituent: UROBILINOGEN
Breakdown of bilirubin in urine(urobilinogenuria) Trace amount of normal Elevated may be due to hemolytic, anemia, infectious hepatitis, biliary obstruction, jaundice, cirrhosis, CHF,infectious mono
118
Summary of abnormal urine constituent: ALBUMIN
In small amount, too large to pass through capillary fenestration Excessive in urine- hyperalbuminuria: Increase permeability due to injury or disease, increase BP, or irritation of kidney cells, by toxins, ETHER or heavy metals
119
Summary of abnormal urine constituent: GLUCOSE
- Presence in urine is GLUCOSuRIA, usually indicates DM | - May be due to stress causing excessive release of epi
120
Summary of abnormal urine constituent: Red Blood cells
The presence of RBCs in the urine: Hematuria | Cause is inflammation of urinary organs as a result of disease, irritation from kidney stones
121
Summary of abnormal urine constituent: KETONE Bodies
High levels of ketone in the body is called ketonuria | Indicated DM, Anorexia, starvation or too little carbohydrates in the diet.
122
Summary of abnormal urine constituent: CASTS
tiny masses of material that have becomes hard and assumed the shape of the lumen of the tubule.
123
Summary of abnormal urine constituent: MICROBES
Specific microbes in the urinary tract.
124
Clearance and GFR What is the best estimate for the functioning of renal tissue________ Other ways are ________ • Creatinine: Provides a good estimate of GFR since only a small amount enters urine.
GFR • Inulin (a fructose polysaccharide) is often used – All inulin filtered is excreted in urine (requires constant infusion to maintain stable plasma level)
125
Creatinine: Provides a __________since only a small amount enters urine.
good estimate of GFR
126
Is a better indicator for hydration status. • Increases in dehydration and kidney failure Normal level
BUN | 7-20
127
Renal clearance
- techniques determine how much of a substance can be cleared from the blood by the kidneys during a given unit of time. – Permits an indirect measure of GFR, tubular secretion, tubular reabsorption, and RBF.
128
The process of urination
Micturition
129
Red Blood cells in the urine
Hematuria
130
The bladder wall muscle
Detrusor
131
Accumulated of precipitated material in the urine that have a cylindral shape like mold of a section of tubule
Casts
132
Precipitated material in urine
Crystals
133
Area of bladder between the opening of the ureters and the urethra
Trigone
134
WBC in urine
Pyuria
135
All of the Glomeruli are located in the
Cortex
136
Principal cells vs Intercalated cells
Principal: secrete K+ and reabsorb sodium and water Intercalated: Reabsorb K+ and secreted H+ ions
137
Tubular secretion vs Tubular absorption
secretion moves substance from the peritubular capillaries to renal tubular lumen Reabsorption moves them from the renal tubular lumen into peritubular capillaries.
138
Renal Hilum
Location where the renal blood vessels, nervs , lymphatics and ureter enter and exit the kidney
139
The BUN level ________ when the GFR decreases
Increases
140
How much a substance can be removed from the blood by the kidney per unit of time
Clearance