安徽医科大学基础医学院：泌尿生殖系统（讲稿）Development of the Urogenital System

Anhui Medical University Development of the Urogenital System Lyu Zhengmei Department of Histology and Embryology Anhui Medical University

Anhui Medical University Development of the Urogenital System Lyu Zhengmei Department of Histology and Embryology Anhui Medical University

Anhui Medical University >ORIGINS-mesoderm -paraxial mesoderm:somite -intermediate mesoderm urinary and genital system -lateral mesoderm paraxial neural intermediate mesoderm groove mesoderm Paraxial Mesoderm Dorsal aorta Intemmediate Mesoderm Somatic mesodem Splanchnic lateral mesodem coelom endoderm notochord mesoderm

Anhui Medical University  ORIGINS-mesoderm -paraxial mesoderm: somite -intermediate mesoderm urinary and genital system -lateral mesoderm neural groove paraxial mesoderm intermediate mesoderm lateral mesoderm endoderm notochord

Anhui Medical University Mesonephros Vitelline duct The Cut line for B origins of origins of Allantois urogenital Meso- urogenital system Future nephrc urogenital system?? duct sinus (bladder) Parameso- nephric D Cloaca duct Future anorectal canal Gonad

Anhui Medical University Part I Introduction The origins of urogenital system?? 【】※ origins of urogenital system

Anhui Medical University differentiation of intermediate mesoderm Mesonephros duct Cut line for B intermediate mesoderm Future duct sinus Nephrotome nephrogenic cord nephric duct Future anorectal canal Gonad urogenital ridge mesonephric ridge,gonadal ridge

Anhui Medical University •intermediate mesoderm Nephrotome nephrogenic cord urogenital ridge mesonephric ridge，gonadal ridge differentiation of intermediate mesoderm

Anhui Medical University 1.Formation of nephrotome Segmented intermediate mesoderm Nephrotome: (pronephric system) Vestigal pronephric The cephalic portion system of intermediate Unsegmented mesoderm becomes intemmediate mesoderm Vitelline (mesonephric system) duct segmented, Mesonephric excretory units which forms Allantois Mesonephric Duct pronephric system Cloaca Unsegmented mesoderm (metan ephric system) and degenerates early

Anhui Medical University Nephrotome: The cephalic portion of intermediate mesoderm becomes segmented, which forms pronephric system and degenerates early. 4 weeks 1.Formation of nephrotome

Anhui Medical University > intermediate 2.Nephrogenic cord mesoderm Segmented intermediate mesoderm (pronephric system) Its caudal part Vestigal pronephric gradually isolated system from somites, Unsegmented intemmediate mesoderm forming two Vitelline (mesonephric system) duct Mesonephric longitudinal excretory units elevation along the Allantois Mesonephric Duct posterior wall of Cloaca Unsegmented mesoderm (metan ephric system) abdominalcavity urogenital ridge

Anhui Medical University  intermediate mesoderm Its caudal part gradually isolated from somites, forming two longitudinal elevation along the posterior wall of abdominal cavity Nephrogenic cord urogenital ridge 2.Nephrogenic cord

Anhui Medical University 3.Urogenital ridge Mesonephros Mesonephric ridge: The outside part of the Vitelline urogenital ridge giving rise to ducty Cut the urinary system line for B Allanto '050 Future Gonadal ridge: nephric urogenital duct sinus (bladder) Parameso. the innerside part giving nephric D Cloaca duct rise to the genital system Future anorectal canal Gonad

Anhui Medical University Mesonephric ridge: The outside part of the urogenital ridge giving rise to the urinary system Gonadal ridge: the innerside part giving rise to the genital system 3. Urogenital ridge

Anhui Medical University >Three sets of kidney occur in embryo developmnet 1)pronephros (2)mesonephros (3)metanephros >Development of Bladder and urethra Cloaca Urogenital sinus >Congenital anomalies of the urinary system

Anhui Medical University Part II Development of Urinary system Three sets of kidney occur in embryo developmnet ( 1)pronephros (2) mesonephros (3) metanephros Development of Bladder and urethra Cloaca Urogenital sinus Congenital anomalies of the urinary system

Anhui Medical University Three sets of kidney systems 1 Pronephros development begins early in fourth week -Pronephros .nonfunctional as a kidney *pronephros attached to Mesonephros pronephric ducts,these ducts are utilized by next set of kidney Cloaca- Metanephros pronephric tubule Metanephric diverticulum Pronephros degenerate in the end of fourth week

Anhui Medical University •pronephric tubule Pronephros degenerate in the end of fourth week Three sets of kidney systems 1 Pronephros •development begins early in fourth week •nonfunctional as a kidney •pronephros attached to pronephric ducts, these ducts are utilized by next set of kidney

Anhui Medical University 2.Mesonephros: Segmented intermediate mesoderm (pronephric system) .Mesonephros begins Vestigial development in mesonephric ridge late in the fourth week Vitelline duct .lie caudal to pronephros Allantois Meso hric syste Cloac Mesonephric duct .large and elongated, Unsegmented mesoderm Ureteric bud (metanephric system) B functional interim,during early embryonic life

Anhui Medical University •lie caudal to pronephros 2. Mesonephros: •Mesonephros begins development in mesonephric ridge late in the fourth week •large and elongated, functional interim, during early embryonic life