Lecture 16: Branching Morphogenesis Flashcards
Types of glands (secretion)
- Serous
- Mucous
- Seromucous
Serous vs mucous secretion
H2O based vs glycoprotein based secretions
Types of glands (structure)
- Unicellular
- Multicellular
-Simple tubular
-Branched compound
Secretory unit shapes
- Tubular
- Alveolar (pit-like)
- Tubulo-alveolar
- Acinar
Types of ducts
- Striated
- Intercalated
- Pancreatic (special centroacinar cell)
Major salivary glands and their secretion types
- Parotid (serous)
- Submandibular (mixed seromucous, 90/10)
- Sublingual (mixed seromucous, 50/50)
Stages of lung development
- Embryonic
- Pseudoglandular
- Canalicular
- Saccular
- Alveolar
Other salivary glands
Minor mucous salivary glands and serous von Ebner’s glands (tongue)
Pancreatic branching
2 trunks form separate dorsal and ventral buds of foregut endoderm
Pancreatic excretory ducts
Duct of Wirsung (ventral bud) and Duct of Santorini (dorsal bud)
Endocrine pancreas cells
Endocrine pancreas = islets of Langerhans
α cells -> glucagon
β cells -> insulin
γ cells -> somatostatin
Pancreatic progenitor lineages
- Tip cells (exocrine acini)
- Trunk cells (ducts, endocrine cells)
Zollinger-Ellison syndrome
Gastrin producing islet cell tumor; gastrinoma
Lung branching
Trachea -> segmental bronchi -> bronchioles -> alveoli
Salivary gland branching
Excretory ducts -> interlobular -> intralobular -> striated -> intercalated -> acinar cells
Pancreatic branching
Excretory ducts (Wirsung, Santorini) -> interlobular -> intralobular -> intercalated -> centroacinar -> acinar cells
Mammary gland branching
Lactiferous ducts -> interlobular -> intralobular -> terminal ductules -> alveolar cells
Kidney development stages
- Pronephros
- Mesonephros
- Metanephros
Kidney branching
Ureters -> major then minor calyces -> collecting duct -> collecting tubules -> nephron
Pancreatic EMT
Trunk cells delaminate (EMT) from the ducts to form islets in mesenchymal tissue
MET events in kidney
- MET from intermediate mesoderm to mesonephric/paramesonephric ducts (to form collecting ducts)
- Induction of metanephric mesenchyme into nephron by metanephric tissue cap via MET
Pronephros
First kidney development stage. Located in dorsal/superior coelomic cavity and drains directly into the cavity. Originates the mesonephric duct.
Mesonephros
Second developmental kidney. Forms internal glomeruli to connect with mesonephric duct
Metanephros
Final, most caudal developmental kidney. Mesonephric duct branches into ureteric bud and collecting tubule/duct.
Metanephric induction of loop of Henle occurs.
Vasculogenesis to form glomeruli and vasa recta occurs.
Formation of renal corpuscle
Vascular supply forms a capillary bed which punches into the primitive renal tubule
