Vorderdarmendoderm

VorderdarmEndoderm refers to the foregut endoderm, the anterior portion of the embryonic endoderm that lines the foregut region of the primitive gut tube. It forms during gastrulation as the endoderm begins to pattern into regional domains, with its identity shaped by interactions with surrounding mesoderm and signaling pathways.

Derivatives of the foregut endoderm include the epithelial lining of the esophagus and stomach, the mucosa of the proximal duodenum, and the liver and biliary system (including hepatic parenchyma, intrahepatic and extrahepatic bile ducts, and gallbladder). The pancreas arises from dorsal and ventral pancreatic buds derived from foregut endoderm, which later rotate and fuse to form the organ. The foregut also gives rise to the respiratory tract via the ventral foregut, forming the larynx, trachea, bronchi, and lung epithelium through the respiratory diverticulum.

Development and organization involve complex signaling between the foregut endoderm and surrounding splanchnic mesenchyme. The liver develops as a hepatic diverticulum from the foregut endoderm, with hepatoblasts differentiating into hepatocytes and cholangiocytes. Pancreatic development involves the dorsal and ventral buds, which converge to create the pancreas. The foregut is typically supplied by the celiac trunk and innervated by the vagus nerves.

The foregut–midgut boundary is clinically relevant; defects in foregut patterning can lead to congenital anomalies such as tracheoesophageal fistula or esophageal atresia.