Chapter 24 Urinary Flashcards
Describe the 3 layers of the kidney.
1-Renal Capsule:prevent kidney infec.
2-Perirenal fat capsule:fat cushioning/body wall attachment
3-Renal Fascia:outer layer anchoring
The major calyces collect, empty, and contain?
Collect urine from papillae
Empty urine to pelvis
Contain contractable smooth muscle (propel urine)
____ amount of blood flows through the kidney per min. and is served via ______ _______ nerve. What fibers regulate renal arteriole diameter?
1/4
renal plexus
sympathetic
What are the two major structural layers that decide what enters the glomerulus?
Glomerular endothelium-fenestrated (no proteins able to pass)
Filtrations slits-feet of podocytes eventually allowing solute into capsular space
The PCT of the renal tubule is composed of? and has what important function?
Microvilli cuboidal cells/mitochondria
reabsorbs water and solutes from filtrate and secretes subs into filtrate
The proximal part of the Loop of Henle is similar to that of? and its two segments are what kind of cells?
PCT
SS Cells (osmosis)
Cuboidal to Columnar Cells (reabsorp)
The DCT is more focused on? and contains what cells?
Secretion than reasorp. cuboidal cells (no microvilli)
The two types of nephrons are called? And are different in what ways?
Cortical Nephron: Most (solute reg.)
Juxtamedullary Neph: Little (essential structure used for production of concentrated urine)
The two cap beds that serve nephrons are?
Glomerulus
Peritubular Caps
Why is blood pressure high in the glomerulus? What occurs because of these 2 reasons?
- Arterioles are high resistance vessels
- Afferent arter. have larger diameters than effer.
Fluid/solute forced out by hydrostatic P throughout glomerulus
Which capillary is low pressure in the nephron? And are adapted for?
Peritubular Cap.
Absorbtion (High Osmotic P)
Name the 3 major kidney functions and 2 additional functions performed.
1-Filter: 200L blood daily
2-Regulate: volume and chemicals
3-Balance: water salt acid/base
4-Gluconeogenesis (sugar from fat/prot): in prolonged fasting
5-Renin/Erythropoetin Production: BP and RBC formation
Afferent arter. will adjust according to BP to protect what? And also effects?
Glomeruli from fluctuations in systematic BP.
Efferent Arter. (reinfor. high glom P and reduces HP in peritub. cap)
Name the three parts to the Juxtaglomerular Apparatus.
Arteriole Walls have JG cells.
Macula Densa
Messanglial Cells
What purpose does the JG cells serve in the arteriole walls?
Granules that contain renin (for when P is down)
Act as mechanorecp (baro) to sense BP
Smooth muscle cells
What purpose do the macula densa cells serve, where are they located?
Chemorecp/osmorec. that respond (measure) dto NaCl in filtrate. (if too high, then kidney filtering to fast, visa versa)
DCT cells
adjacent to JG cells
What is the function of Mesanglial cells?
phagocytic/contractile properties.
influence cap. filtration.
(free debris from slits on podocytes)
Name and describe the 3 layers of the filtration membrane (divider of blood and glom capsule).
Fenestrated endothelium of the glomerular caps
Visceral membrane of the glom cap (podocytes)
Basement membrane of fused basal laminae
The kidneys filter the bodys entire plasma volume __ times a day and consume___%-___% of the bodys oxygen.
60
20-25
The component of urine is _______ and this is made where, how?
urea
liver
protein catabolism
What three major processes are involved in urine formation and blood composition adjustment?
Glomerular Filtration (fluid/solutes move from glom to cap space)
Tubular Reabsorption (PCT to peritubular cap)
Tubular Secretion (DCT) *selectively based on blood comp (peritub cap) to eliminate/remove excess, such as too much Na or H2O
What is GFR? and factors of filtration rate at cap bed?
total amount of filtrate formed per minute by the kidneys
- surface area
- filt. mem. permeability
- NFP (net filtration P)*GFR directly proportional to this
GFR and NFP will change with any BP changes.
If GFR is too high what is the problem? too low?
Needed subs not reabsorbed fast enough and lost in urine.
Everything reabsorbed (including wastes)
*Intrinsic
How would liver dz affect renal function?
OP at the caps affected not allowing efficient reabsorption because the liver not producing plasma proteins needed, leading to dehydration
What are the 3 mechanisms that control GFR.
Renal autoregulation (intrinsic normal conditions)
Neural controls (sns)
Hormonal mechanisms (renin-angio system)
The intrinsic autoregulation of GFR entails 2 types of control:
Myogenic-vascular smooth muscle (maintain normal blood F)
Flow-dependent tubuloglomerular feedback-Juxtamedullary apparatus (MACULA DENSA release chems to vasoconst (renin) or vasodil as needed *neg fb sys)
The neural controls that control GFR do what at rest? under stress?
REST: renal blood vessels are max dilated,
autoreg mechs prevail (long term surv).
STRESS: NorEPI release by SNS, EPI release by adrenal medulla, afferent arter constrict, FILTRATION inhibited.
SNS also stims JG cells release renin, then renin-angio mech begins.
What 4 factors can trigger renin release of JG cells?
1-reduced stretch of JG cells 2-mac dens stimulation 3-SNS B1 adrenergic receptors 4-angiotensin II *solution is more pressure for kidneys to continue working
In healthy kidneys, what is reabsorbed? Water and ion reabsorb. is _________ controlled. Reabsorb can be _______ or _______ transport processes.
All organic nutrients
hormonally
active
passive
Reabsorption transport of solutes pathway can be either _____ cellular or _____ cellular. Meaning?
Name the 3 types.
trans-thru membrane or para-thru tight junction
- Primary active:ATP carries molecule
- Sec. active: concen gradient made by PRIM ACT transport allowing free pass thru
- Passive:moves with water, or diffusion down conc. grad.
What is osmolarity?
total concentration of ALL solutes in solution (attracts water)
Describe the Na+ glucose cotransport carrier.
Secondary active pulling a glucose in with every sodium to cells.
WITHOUT THIS MECHANISM-100% of glucose reabsorption is impossible.
What occurs in the descending loop of henle?
(simple cuboidal becomes simp squam)
Membrane permeable to H2O only
Water diffuses out, solutes concentrate making osmolarity increase!
What happens in the ascending loop of henle?
water stays in, solutes pumped out of tubule, filtrate diluted, osmolarity decreases.
Substances are not reabsorbed if they:
What are the most important nonreabsorb subs?
If all carriers are sat, excess excreted -lack carriers -not lipid soluble -too large to pass membrane pores Urea, creatinine, and uric acid
Diuretics are chemicals that
do not reabsorb
exceed ability of renal tubules to reabsorb it (glucose for diabetics)
Inhibit Na+ reabsorb.
Osmotic diuretics include:
High glucose levels-carries water out with glucose
Alcohol-inhibits ADH
Caffeine- inhibit sodium ion reabsorp
Lasix/diuril-inhibit Na+ associated symporters
What is a renal clearance test used for?
Determine GFR
Detect glomerular damage
Follow progress of diagnosed renal dz
What is the substance inulin (for renal clearance) used for and how?
What does the result values determine?
determine GFR (normal 125ml/min)
Injected (IV) polysacc that is freely filtered and neither reabsorbed or secreted by kidney.
CV below inulin (125) means substance is partially absorbed (urea)
CV at 0 means sub completely reabsorbed (glucose)
CV above inulin means tubule cells secreted sub into filtrate (drug metab such as propanolol)
What are the layers of the ureter? (similar to bladder)
Transitional epith mucosa
Smooth muscle muscularis
Fibrous conn tiss adventitia
What are the 3 sphincters involved with the urethra?
Internal urethral sphin-involuntary at bladder-urethra junction
External urethra sphin-voluntary at urogenital diaphragm
Levator ani muscle-voluntary urethral muscle (anus)
What are the 3 urethra regions of the male?
Prostatic urethra-runs within the prostate gland
Membranous urethra-runs through the urogenital diaphragm
Spongy urethra-passes through the penis and opens via the external urethral orifice
What is renal calculi? How is it caused? What is one way to treat?
Kidney stones
crystallization of calcium or magnesium salts in renal pelvis
Shock wave lithotripsy-smash stone
What are some symptoms of UTI?
dysuria (burning), urinary urgency, fever, cloudy or blood-tinged urine
What is incontinence? Retention?
Involuntary discharge of urine
bladder is unable to expel its contents
