Mesenchyme

From Freepedia

Mesenchyme (also known as embryonic connective tissue) is the mass of tissue that develops mainly from the mesoderm (the middle layer of the trilaminar germ disc) of an embryo. It later becomes differentiated into blood vessels and blood-related organs such as the spleen, and into connective tissues.

Embryonic connective tissue (mesenchyme)

• a. Stained with Hematoxylin and Eosin.
• b. Reveals a pink/purple appearance.
• c. Mesenchyme
  • i. Connective tissue originates from the mesenchyme, an embryonic tissue formed by elongated cells, the mesenchymal cells.
    • 1. Mesenchyme develops into other types of structures, such as blood cells, endothelial cells, and smooth muscle cells.
  • ii. Mesenchyme develops from the middle layer of the embryo, the mesoderm.
  • iii. Consists of mesenchymal cells and fine reticular fibers interspersed in a semi-fluid matrix of ground substance.
  • iv. Note that mucous connective tissue is also embryonic tissue.
    • 1. It is more viscous in consistency, contains collagen bundles and numerous fibroblasts, and is found deep to the fetal skin and in the umbilical cord (Wharton’s jelly), surrounding the umbilical vessels.