Renal Anatomy & Histology Flashcards by Priscilla Vu

Organs of the urinary system and function

kidneys, ureters, urinary bladder, and
urethra

Kidneys filter metabolic waste products and toxins from the bloodstream and convert the filtrate into urine; important
role in BP regulation

The ureters, urinary bladder, and
urethra make up the urinary tract
because they store and transport the urine out of the body

How well did you know this?

Not at all

Perfectly

Characteristics of Anterior Aspect (location, size, what does it contain)

Retroperitoneal lying about T12-L3 levels

Lower on right

Suprarenal gland above

Size—10 cm long, 5 cm wide, & 2 cm thick

Renal hilum—entrance to renal sinus (area in kidney where BV, renal pelvis, nerves are locate)

How well did you know this?

Not at all

Perfectly

Characteristics of Posterior Aspects (plane , what does it contain)

Left hilum near transpyloric plane (—5 cm from median plane)

Transpyloric plane runs through superior pole of right kidney (—2.5 cm lower than left)

Posteriorly, superior parts lie deep to 11th and 12th ribs

Inferior pole of right kidney is approximately index fingers breath superior to iliac crest

How well did you know this?

Not at all

Perfectly

Renal Fat (3)

1) Perinephric fat-adjacent kidney
- extends into renal hilum and pelvis

2) Renal fascia— covers fat enveloping kidney and suprarenal gland
- blends and sheaths renal vessels
- superiorly continuous with inferior diaphragmatic fascia
3) Paranephric fat—external to renal fascia

How well did you know this?

Not at all

Perfectly

internal anatomy of kidney (9)

1) Capsule—dense irregular CT on surface with inner layer of myofibroblasts
2) Renal cortex—outer portion containing renal corpuscles
3) Renal medulla—collection of renal pyramids and columns
4) Renal pyramids—cone-shaped masses in the medulla projecting into calyx
5) Renal columns—tissue lying between pyramids running from cortex to the calyx
6) Renal lobes—single pyramids plus surrounding adjacent cortex
7) Renal pelvis—collecting funnel for urine
8) Renal calyxes—out-pocketings of the renal pelvis
9) Renal papillae- projections of medullary pyramids apices into calyxes

How well did you know this?

Not at all

Perfectly

Renal artery (1) and Ureter branches (6)

Renal arteries
• Segmental arteries

Ureter

1) Renal branches
2) Gonadal branches
3) abdominal aorta branches
4) Iliac branches
5) Superior vesicular branches
6) Pelvic branches- rectal, uterine, vaginal, inferior vesicular

How well did you know this?

Not at all

Perfectly

Path of renal blood supply

aorta-> renal artery-> segmental artery-> interlobar artery -> arcuate artery-> cortical radiate artery-> afferent arteriole-> glomerulus (capillaries)-> efferent arteriole-> peritubular capillaries and vasa recta-> cortical radiate vein-> arcuate vein-> interlobar vein-> renal vein-> inferior vena cava

How well did you know this?

Not at all

Perfectly

Renal nerve plexus (innervation)

Sympathetic: aorticorenal ganglia

Lesser Splanchnic (T10-T11)
Least Splanchnic ( T12)
Lumbar splanchnic ( L1-L2)

Parasympathetic
- vagus n

How well did you know this?

Not at all

Perfectly

What is Urine Carrying Unit made up of? (2)

1) Nephron (urine forming unit)- renal corpuscle and renal tubule
2) cortical and medullar collecting ducts- final concentration of urine

How well did you know this?

Not at all

Perfectly

Renal Tubular Structures (12)

Bowman's capsule
Proximal convoluted tubule
Proximal straight tubule
Thin loop of Henle (x2)
Thick ascending loop of Henle
Macula densa location 
Distal Convoluted Tubule
Collecting Tubule
Collecting Duct- Cortical
Collecting duct- Medullary 
Papillary Duct

How well did you know this?

Not at all

Perfectly

What does the cortex contain?

renal corpuscles
convoluted tubules
Straight tubules
portions of collecting ducts

How well did you know this?

Not at all

Perfectly

What does medulla contain?

renal pyramids ( cone-shaped masses)

Renal columns

How well did you know this?

Not at all

Perfectly

What are cortical (medullary) rays? and what do they contain?

aggregation of collecting ducts and straight tubules

runs between renal corpuscle and convoluted tubules within cortex

axis of renal lobule

How well did you know this?

Not at all

Perfectly

What is renal interstitium?

Fibroblasts that produce erythropoietin depending on O2 levels

How well did you know this?

Not at all

Perfectly

Renal Corpuscle components ( 2 , layers)

1) Glomerulus
- capillaries (tuft)
- fenestrated with truly open pores
- afferent and efferent arterioles

2) Glomerular capsule (Bowmans)
- parietal layer- simple squamous
- visceral layer- podocytes
- glomerular space- primary filtrate

How well did you know this?

Not at all

Perfectly

Poles of renal corpuscle (2)

Study These Flashcards

Vascular pole

afferent arteriole
efferent arteriole

Urinary pole
- origin of proximal convoluted tubule

Glomerular Endothelium characteristics (4)

Study These Flashcards

truly open fenestrations
thick luminal glycocalyx
lots of aquaporin water channels
can generate Nitric oxide and PGE2 ( via angiotensin II)

podocytes characteristics (4)

Study These Flashcards

visceral layer of Bowman’s

forms part of filtration barrier
single layer of cells having foot-like process (pedicels) that interdigitate to make filtration-like slits

-slits important for regulating size, patency, and selectivity of filtration

Filtration Membrane ( location, functions, layers (4))

Study These Flashcards

lies between blood and capsular space

FXN:

restricts passage of blood cells, immunoglobulins and large proteins
allows passage of water, ions, glucose, amino acids, urea
one quart passes through per 8 mins ( ~45 gallons per day) but 1 gallon excreted per day

plasma

1) capillary endothelium
2) basement membrane
3) foot processes of glomerular capsule
4) slit diaphragm

Glomerular Basement (content, barriers)

Study These Flashcards

Type IV and XVIII collagen, laminin, entactin, proteoglycans
physical barrier- <70kd passes through
chemical barrier - strong anti-anionic characteristics
albuminia: urine albumin will show damaged GBM

Mesangial cells function (5)

Study These Flashcards

FXN:

1) support glomerular loops and ECM of podocytes
2) control glomerular filtration rate
3) prevent glomerular distension ( contractile) due to high glomerular BO
4) secrete growth factors and cytokines in response to injury
5) phagocytic- removing cellular debris and protein aggregates

Proximal Convoluted Tubule

location, tissue, content

Study These Flashcards

in renal cortex
most abundant and active tubule in resorption and secretion
simple cuboidal/columnar
lots of microvilli and mitochondria
basal and lateral cell membranes
increase SA
Na/K Atpase pumps and aquaporins
Glucose transporters (sGLT2) and amino acid transporters

Proximal Straight Tubule

Study These Flashcards

less well-developed brush border

- high affinity sodium-glucose cotransporter (sGLT1)

Loop of Henle (path, tissue, function) for thin and thick

Study These Flashcards

Path- down into medulla, up into cortex, terminates near vascular pole

Thin

simple squamous
no brush border
some nuclei bulge into lumen

Thick

simple cuboidal
microvilli
no brush border

FXN:
- set up hyper osmotic gradient to draw water back into tubule

distal convoluted tubule (location, tissue, hormone)

- cortex - from macula densa of thick ascending Loop of Henle portion - simple cuboidal epithelium - little microvilli - smooth luminal surface - cells taller than Thick ascending LOH - Angiotensin II influences Na+ resorption

Collecting duct ( tissue, location, function (2), cell types (2), hormone)

- simple cuboidal (some simple columnar) - through cortex into deep medulla - form larger papillary ducts that then drain into renal minor calyx FXN: 1) water reabsorption 2) receive primitive urine from several nephron - final urine osmolality determined by resorbing H2O - individual cells of duct epithelium can be detected Cell Types 1) Light/Principal cells- target for aldosterone 2) Dark/Intercalated cells- involved H+ and bicarbonate transport Hormones - target of both ADH and aldosterone - increasing Na+ reabsorption and water retention

Types of Capillary Beds (3)

1) Glomerulus- high to low pressure gradient ( afferent arterioles drained by efferent arterioles) 2) Peritubular capillaries - from efferent arterioles - surround convoluted tubules - lined with fenestrated endothelium - reuptake of H2O and salts 3) Vasa Recta - thin-walled vessels - arise from efferent arterioles of juxtamedullary glomeruli - fenestrated in ASCENDING only - run alongside loop of Henle - part of urine concentrating system

Juxtaglomerular Apparatus (components (2))

1) Juxtaglomerular cells - mechanosensory - secrete renin if BP is low 2) Macula Densa - distal end of thick ascending LOH - acts as chemoreceptor (monitor salt levels) - signal release of renin from juxtaglomerular cells if sodium is low

Function of Renin

Increase sodium retention, blood volume, and blood pressure

Transitional Epithelium (location, layers, content)

- lines urinary tract Layers 1) superficial- stretched and relaxed 2) intermediate- sliding layer 3) basal- stem cell (epithelial) Fusiform vesicle - fuse with plasma membrane when cell is distended - endocytosed when nondistended Urothelial plaque - form impermeable barrier - uroplakin proteins

Ureters (location, function, tissue, layer)

- long fibromuscular tube - carry urine from kidney to bladder - renal pelvis-> bladder - goes oblique to prevent backflow of urine - transitional epithelium Muscularis ( 3 layers) 1) inner longitudinal layer 2) outer circular layer 3) outer longitudinal layer Adventitia - typical connective tissue

Urinary Bladder ( characteristic, function, location, content)

- muscular sac - posterior to pubis - anterior to uterus/rectus - expands into abdominal cavity while empty bladder lies entirely within pelvis - store and expel urine Trigone - inferior/posterior wall - ureter and urethra open Bladder wall - transitional epithelium - 3 layer thick smooth muscle (detrusor muscle) - fibrous adventitia

Urethra ( General function, tissue)

- connect bladder with exterior Epithelium depends on location - Transitional epithelium- near bladder near origin (proximal) - Pseudo stratified columnar- majority of Urethra - Stratified Squamous Epithelium- at distal end

female urethra (length, path, components (3), function)

size: 3-5 cm external urethral orifice (female perineum) 1) Membranous urethra- through urogenital diaphragm 2) Internal urethral sphincter- INVOLUNTARY SMOOTH muscle, part of bladder wall 3) external urethral sphincter- VOLUNTARY SKELETAL muscle inhibit urination , part of pelvic floor Function - restrict release of urine until pressure in urinary bladder is high enough - voluntary activity to release urine

Male Urethra ( size, function (2), regions (3))

size: 20cm in length function 1) transport urine 2) transport semen Regions 1) Prostatic urethra- passes through prostate gland 2) Membranous urethra- through urogenital diaphragm ( same in female) 3) spongy (penile) urethra - passes length of penis - encased in cylindrical erectile tissue (corpus spongiosum) in penis to reach external urethral oriface

polycystic kidney disease

Autosomal Dominant Cysts form - crush tissue and impede drainage - kidney failure/ infection - BP mis-regulation - asymptomatic - first seen at 30-40 yr Tx: - major diet change - kidney transplant - dialysis

Renal Anatomy & Histology Flashcards

(36 cards)