Development of Urinary system and reproductive system 1

Development of Urinary system and reproductive system 1. Development of kidney and ureter 2. Development of urinary bladder and urethra 3. Abnormality in urinary system 4. Development of gonad 5. Development of reproductive tracts 6. Abnormality in reproductive system

3 rd week: Head segmentation Nephrotome → Intermediate Mesoderm Pronephros Other migration, proliferation Nephrogenic cord → Mesonephros and Metanephros

Intermediate mesoderm ─── 3 rd week ─────→ Mesonephric ridge Gonadial ridge Intermediate mesoderm Nephrogenic cord ───→ Urogenital ridge Urinary system, Genital excurrent ducts Gonad Pudendum

Mesonephric ridge Urogenital ridge Gonadial ridge

Mesonephric ridge Gonadial ridge

Development of urinary system Development of kidney and ureter 1. Pronephros 4 th week Nephrotome (7 -14 th Somite) Pronephric tubule duct Degeneration in 1 week Mesonephric duct

Pronephric tubule Pronephros Time： 4 th week Function：no Destiny: degeneration

2. Mesonephros 14 -18 th somite Middle part of nephrogenic cord 80 transverse Sshaped tubule Mesonephric tubule Inner end form renal capsule Glomerulus Outer end bind to mesonephric duct Mesonephric duct The end bind to cloaca Continus to pronephric duct

Time： end of 4 th week Function: Mesonephric duct transient urinary Mesonephric tubule Destiny: Most degeneration, Small part form male excurrent duct

3. Metanephros Time：begin at 5 th week, exist forever Function：begin at 3 th month, urinary function Position：rise gradually Metanephros

End of （adjacent to cloaca） mesonephric duct Origin Ureteric bud one Prolong Ureter Embranchment ＞ 12 Renal pelvis, renal calyce （The end branched as T） Collecting tube

Origin two Metanephrogenic blastema (Mesoderm of the mesonephric ridge) Cap-shaped cell cluster S-shaped tubule Bind to collecting tubule Renal capsule Glomerulus Renal tubule + Renal corpuscle Nephron

Mesonephric tubule Ureteric bud Metanephrogenic blastema Renal pelvis calyce Collecting tubule

Formation and rising of metanephros

Development of urinary bladder and urethra Male Upper： Urogenital Cloaca 4 -7 th week Urorectal septum sinus Middle: Female Urinary bladder Urinary Upper part Urethra bladder of urethra Anorectal canal Lower: Lower part of urethra Vestibule of vagina

Evolvement of male urogenital sinus A C B D E

Positional evolvement of Ureter and Mesonephric duct Ureter Mesonephric duct

Abnormality • • • Polycystic kidney Horseshoe kidney Single kidney • • • Double ureter Urachal fistula Exstrophy of bladder

Polycystic kidney

Horseshoe kidney

Single kidney Right single kidney Left single kidney

Ectopic kidney

Double ureter Ureter

Urachal fistula

Exstrophy of bladder

Development of gonad Gonad differentiation at 7 th week Developmental stage： Sex undifferentiated stage→ Sex differentiated stage Reproductive tracts：２ → Proper current： １ → Feamle

Development of gonad Endoderm cells of yolk sac １. Development of undifferentiated gonad 4 th week Proliferation, differentiation Primordial germ cells 6 th week Gonadial ridge 6 th week Superficial epithelium →cell cords Migration in one week Primary sex cord

Primordial germ cells Large and round endoderm cells in yolk sac

Migration of primordial germ cells 6 th week

Histocompatibility Y antigen § H-Y antigen determine the differentiation to testis The gene of H-Y antigen located at Y chromosome The cell membrane of the cell which sex chromosome is XY possesses H-Y antigen § Primary sex cord H-Y antigen proliferation seminiferous tubule

２. Development of testis Primary sex cord (H-Y antigen) 7 th week Separated from surface Mesenchymal cell Cells of sex cord Primordial germ cells Interstitial cell + Sustantacular cell + Spermatogonium Testis

３. Development of ovary Superficial epithelium (No H-Y antigen) Mesenchymal cells Primary sex Secondary sex cord (cortical cord) cord After 10 th 16 th week Primordial follicle Degeneration Cells of sex cord Stroma + Follicular cells Primordial germ cells + Oogonium Ovary

Cortex Medulla Cortical Cord Testis Ovary Rete testis Tubule rectus Follicle Seminiferous tubule

Testis Rete testis Ovary Tubule rectus Follicle Seminiferous tubule Spermatogonium Primary oocyte Sustantacular cell Follicular cell Seminiferous tubule Follicle

４. Descend of testis and ovary Embryo →lengthen Gubernaculum →shorten 7 th to 8 th month → Scrotum

Development of reproductive tracts 1. Undifferentiated stage: Mesonephric tubule Gonad Mesonephric duct Sinus tubercle A. Male Paramesonephric tubule Urogenital sinus B. Female

２. Differentiation of female reproductive tract Paramesonephric duct： End of upper segment：Fimbria Upper and middle segment：oviduct Lower segment： Uterus End： Sinus tubercle： Vaginal plate Mesonephric ducts and tubules Vaginal fornix Vagina Degeneration

3. Differentiation of male reproductive tract Metanephric Head ── Epididymal duct Tail ── Spermaduct Mespnephric tubules Most of →degeneration Some of → Efferent ducts Paramesonephric duct Degeneration

Ovary Testis Urogenital sinus Spermaduct Urogenital sinus Oviduct Uterus Vaginal plate Efferent duct Epididymal duct

Abnormality of reproductive system 1. Cryptorchidism 2. Congenital inguinal hernia 3. Double uterus 4. Vaginal atresia 5. Hypospadias 6. Hermaphroditism

Cryptorchidism

Congenital inguinal hernia

Double uterus

Vaginal atresia

Hypospadias

Hermaphroditism