Changes in the extracellular matrix and glycosaminoglycan synthesis during the initiation of regeneration in adult newt forelimbs
The extracellular matrix (ECM) of the distal tissues in a newt limb stump is completely reorganized in the 2-3-week period following amputation. In view of numerous in vitro studies showing that extracellular material influences cellular migration and proliferation, it is likely that the changes in the limb's ECM are important activities in the process leading to regeneration of such limbs. Using biochemical, autoradiographic, and histochemical techniques we studied temporal and spatial differences in the synthesis of glycosaminoglycans (GAGs) during the early, nerve-dependent phase of limb regeneration. Hyaluronic acid synthesis began with the onset of tissue dedifferentiation, became maximal within 1 weeks, and continued throughout the period of active cell proliferation. Chondroitin sulfate synthesis began somewhat later, increased steadily, and reached very high levels during chondrogenesis. During the first 10 days after amputation, distributions of sulfated and nonsulfated GAGs were both uniform throughout dedifferentiating tissues, except for a heavier localization near the bone. Since nerves are necessary to promote the regenerative process, we examined the neural influence on synthesis and accumulation of extracellular GAGs. Denervation decreased GAG production in all parts of the limb stump by approximately 50%. Newt dorsal root ganglia and brain-derived fibroblast growth factor each produced twofold stimulation of GAG synthesis in cultured 7-day regenerates. The latter effect was primarily on synthesis of hyaluronic acid. The results indicate that the trophic action of nerves on amphibian limb regeneration includes a positive influence on synthesis and extracellular accumulation of GAGs.
- Research Organization:
- Indiana Univ., Bloomington
- OSTI ID:
- 5623669
- Journal Information:
- Anat. Rec.; (United States), Vol. 4
- Country of Publication:
- United States
- Language:
- English
Similar Records
Injury, nerve, and wound epidermis related electrophoretic and fluorographic protein patterns in forelimbs of adult newts
Hyaluronic acid production and hyaluronidase activity in the newt iris during lens regeneration
Related Subjects
GLUCOPROTEINS
BIOSYNTHESIS
LIMBS
BIOLOGICAL REGENERATION
ACETATES
AUTORADIOGRAPHY
CELL DIFFERENTIATION
CELL PROLIFERATION
CHONDROITIN
HYALURONIC ACID
NERVES
NERVOUS SYSTEM
SALAMANDERS
AMINES
AMPHIBIANS
ANIMALS
AQUATIC ORGANISMS
BIOLOGICAL RECOVERY
BODY
BODY AREAS
CARBOHYDRATES
CARBOXYLIC ACID SALTS
MUCOPOLYSACCHARIDES
ORGANIC COMPOUNDS
POLYSACCHARIDES
PROTEINS
RECOVERY
SACCHARIDES
SYNTHESIS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques