Embryo Flashcards
What are the 3 most important genes in the embryogenesis of the kidney?
- Pax 2 (differentiation of Urogenital ridge)
- WT1 (nephroblastoma)
- GDNF (agenesis of kidney aka Potter Syndrome)
Genital and renal system develop intimately together from wich embryologic tissue lineage?
The intermediate mesoderm
In which sequence does the renal system develop?
In a cranio-caudal sequence
What are the 4 main steps of the formation of the metanephric Kidney?
- Pronephros
- Mesonephros
- Metanephros
- Displacement of gonads downward to its definitive sites and definitive kidney upward to its definite site (L1-2 region) .
What happens during pronephros?
It is a transitory structure (3-4th week) that will form the cranial suspensory ligamentous structure (important during gonad development).
What happens during mesonephros?
During the 4th week and is functional as it forms embryonic urine that is passed via the cloaca into the amniotic fluid. It is the side of nephric duct formation (caudal growth).
- The primitive gut end in the endodermal Cloaca, which is later split into an anterior Urogenital sinus (bladder, urethra) and posterior ano-rectal canal.
- The mesonephric duct (and ureter) empties into the Urogenital Sinus.
What happens during metanephros?
During the late 4th week-5th week is induced in the caudal pelvic region. The site of metanephric kidneys formation is determined by the specific gene expression of GDNF by the metanephric mesenchyme trough MET and conversion-extension mouvement.
The Collecting Duct System is formed by sequential Bifurcation of the Ureteric Bud. Ureteric Bud forms: (1) ureter (2) renal pelvis (3) major calyces (4) Minor calyces (5) collecting tubules. Metanephric mesenchyme forms: nephrons (continues after birth).
What is that?
Double Collecting duct system in a single kidney
What is that?
A single kidney
What is that?
Double kidney that merged
What is that?
Polycystic kidney (lobulated ) newborn
What is that?
Horseshoe Kidney
