Development of GI system

1. Development of GI system 陳建榮 http://web.nchu.edu.tw/pweb/index2.php?pid=75

3. GI system: • Primitive Gut Morphogenesis • Foregut • Midgut • Hindgut • Foregut embryology • Midgut embryology • Hindgut embryology 

4. Formation of primitive gut Head fold, tail fold and lateral fold • Foregut • Midgut • Hindgut

5. Primitive gut:

6. The primitive gut: • Foregut 前腸 • esophagus • stomach(S) • proximal half of the duodenum (PD), • liver and pancreas. • Midgut 中腸 • distal half of the duodenum(DD) • jejunum(J), • ileum(I), • cecum(C), • appendix, • ascending colon and the right 3/4 of the transverse colon. • Hindgut 後腸 • left 1/4 of the transverse colon • the descending colon • sigmoid colon • the rectum(R) down to the ano-rectal line (the endoderm-ectoderm junction).

7. The blood supply: • Foregut : celiac artery • Midgut :superior mesenteric artery • Hindgut :inferior mesenteric artery The venous drainage of the gut : • Foregut : portal vein • Midgut : superior mesenteric vein • Hindgut :inferior mesenteric vein.

9. Functional divisions of primitive GI system

10. GI system: • Primitive Gut Morphogenesis  • Foregut Embryology • Development of stomach • Development of mesentery • Liver morphogenesis • Pancrease morphogenesis • Midgut embryology • Hindgut embryology 

11. Development of stomach Stomach: • Clock wise 90 • Greater curvature of stomach胃大彎 • Lesser curvature of stomach胃小彎 • Vagus n.

12. Development of stomach

13. Development of stomach

14. GI system: • Primitive Gut Morphogenesis • Mesentery morphogenesis • Dorsal mesentery背總腸繫膜 • Ventral mesentery腹總腸繫膜 • Foregut Embryology • Midgut embryology • Hindgut embryology 

16. Formation of Greater omentum大網膜

17. 網膜孔 網膜囊

26. THE MESENTERY:-ventral mesentery: -falciform lig.鐮狀韌帶 -lesser omentum小網膜 -coronary lig.冠狀韌帶 -triangular lig.三角韌帶 -dorsal mesentery: • Mesogastrium : greater omentum大網膜, omentum bursa網膜囊 • Mesoduodenum十二指膜系膜 • mesentery proper (distal duodenum, jejunum and ileum), • mesocolon 結腸系膜 • Mesorectum直腸系膜

27. 5 weeks 4 weeks Development of liver: • Hepatic diverticulum肝憩室 • Hepatic cords 肝索 • Gallbladder膽囊 • Ventral pancreatic bud腹側胰芽 5 weeks 6 weeks

29. Development of pancrease • Dorsal pancreatic bud背側胰芽 • Body and tail of pancrease, accessory pancreatic duct • Ventral pancreatic bud腹側胰芽 • Uncinate process of pancrase, main pancreatic duct

30. Clinical problems Annular pancrease環狀胰臟

31. Duodenal stenosis or atresia十二指腸栓塞或狹窄

32. Development of spleen Accessory spleen副脾

33. GI system: • Primitive Gut Morphogenesis  • Foregut Embryology • Midgut embryology • Rotation of midgut loop • Retum of midgut to abdomen • Fixation of intestine • Cecum and appendix • Hindgut embryology 

36. 6 weeks Rotation of midgut loop - Counterclock wise 90 10 weeks Retum of midgut to abdomen 11 weeks

37. Midgut development of animals

38. Midgut development of animals

40. Clinical problems Umbilical hernia ↑ ↓ Gastroschisis Muscles of abdominal wall : normal

41. Gastroschisis 裂腹畸形(前腹壁缺損)

42. Nonrotation of midgut Mixed rotation and volvulus Reversed rotation Internal hernia Midgut volvulus

43. Fixation of intestine

44. Cecum and appendix

46. Clinical problems Meckel’s diverticulum梅爾氏憩室

47. Ileal diverticulum迴腸憩室

48. Duplication of intestine腸重覆

49. GI system: • Primitive Gut Morphogenesis  • Foregut Embryology • Midgut embryology • Hindgut embryology • Partitioning of cloaca泄殖腔 • Urorectal septum泌尿直腸隔 • Cloaca泄殖腔 • Urogenital sinus泌尿生殖竇 • Anal canal肛管