Renal Embryology - Dennis Flashcards
kidneys and gonads come from what
intermediate mesenchyme (mesoderm)
urogenital ridge comes from what and forms what
each side of the dorsal aorta
forms the nephrogenic cord which makes the pronephros, mesonephros, metanephros
when do the pronephros come and where
week 4
cervical region running caudally into the cloaca
pronephros degenerates when and what stays
day 24-25
pronephric duct stays to make mesonephros
when do mesonephros come and where
late week 4
caudal to pronephros
has ducts and then tubules
what do mesonephric ducts and tubules make
tubules connect to the vesicle become renal corpuscles = glomerular capsule
when do mesonephros function as kidney and when does it degenerate
week 6-10 (for baby)
degenerates in females week 12
becomes efferent ductule in makes week 12
trigone of bladder part is the only part that stays
when does the metanephros come and where and 2 parts to it
week 5
caudally to mesonephric duct
1. causes mesonephric duct to make ureteric bud
2. metanephric blastema forms around the bud
ureteric bud is from what
mesonephric duct
metanephric blastema is from what
nephrogenic cord
when is the metanephros a functional kidney
week 9-10
how does the renal pelvis form
the ureteric bud elongates and penetrates the blastema
things that come from ureteric bud
ureter, renal pelvis, minor and major calices, CD*
things that come from the blastoma
PT, LOH, DCT, glomerular capsule
how do the blastema form its parts
- vesicle forms under the ureteric bud
- vesicle elongates = metanephric tubules
- end of tubule forms glomerular capsule (proximal)
- distal end of tubule becomes DCT
where are the permanent kidneys in the body and how do they move
they ascend indirectly by everything else in the embryo descending WEEK 9
how does the vasculature form in the developing permanent kidney
- hilum rotates medially 90 degrees
- BV from common iliac
- as kidney ascends the BVs degenerate and BVs from ABD aorta =renal arteries
when do suprarenal glands form
after kidney has ascended week 9
Accessory Renal Vessels
more then one renal artery (25% of people)
can obstruct ureter and = hydronephrosis
** need to be cautious in surgery, if ligated or damaged can cause ischemia)
Unilateral Renal Agenesis
usually asymptomatic
embryo has one umbilical artery, umbilical bud does not form on one side
(can cause oligohydrominos)
Bilateral Renal Agenesis
oligohydramnios
pulmonary hypoplasia, clubbed feet and hands, Potters syndrome
Ureter Duplications
ureteric bud divides abnormally
more then 1 ureter
if complete = both kidneys have 2 ureters or bifid
Horseshoe Kidney
inferior pole of kidney where isthmus is is connected on the back = 1 kidney
- usually asymptomatic
- can cause X ascending of kidney due to it getting stuck on the IMA
- can be issue in pregnancy
Polycystic Kidney Disease
mutation in PKHD1
cysts in both kidneys and many
renal insufficiency
25 % come from pulmonary hypoplasia
Multicystic Dysplastic Kidney
cysts (dilated LOH) on usually only one kidney and not as many
not as severe
where is the urogenital sinus and anorectal canal
ventral cloaca
what separates the urogenital sinus and anorectal canal
urorectal septum
3 parts of urogenital sinus
- Vesical part : bladder
- Pelvic part : urethra
- Phallic part : vagina and spongy urethra
how does the bladder form as attaches to ureter and urethra
- mesonephric duct incorporates to posterior wall
- it extends to urethra and ureter
- it forms trigone
how is the medial umbilical lig formed
- the allantois is connected to bladder
- constricts and becomes urachus
- connects to umbilicus from apex of bladder
- forms fibrous tissue closing the tube
- MUL
epithelium of bladder
endoderm (urogenital sinus)
submucosa and muscularis of bladder
splanchnic mesoderm
Trigone of bladder
intermediate mesoderm (mesonephric ducts)
Exstrophy of bladder
week 4 problem when bladder folds and is inverted
mucosa is exposed out into amniotic fluid and makes posterior wall of bladder red
Epispadias
urethra opens on dorsum of genital tubercle (males)
urachal cysts
remanent of urachal epithelial lining in some part
= can get enlarged and inflamed
Urachal sinus
end part of urachus remains unclosed by fibrous tissue
and urine can at times discharge out from umbillicus
urachal fistula
entire urachus is open and no fibrous tissue
urine can escape from umbilicus
medulla of suprarenal gland
chromaffin cells : NE and E
cortex of suprarenal glands
Zona Glomerulosa : mineralocorticoids
Zone Fasiculata : glucocorticoids
Zone Reticularis : Sex
medulla of SRG forms from
NCC —-> middle of the developing fetal cortex
Fetal Cortex of SRG forms from
coelmic epithelium entering surrounding mesoderm on the urogenital ridge
fetal cortex degenerates when
2nd month
and adult cortex forms with all the layers
fetal cortex secretes what
DHEA —-> placenta converts it to Estradiol = for pregnancy health
ACTH and glucocorticoids (also in adults)
