Sam Schmidt Paralysis Foundation a cell body, which houses the nucleus. Axons and dendrites form extensions from the cell body. Glial cells are "nerve-helper" cells that provide structural support, nourishment and protection for neurons. Astrocytes, a kind of glial cell, are the primary support cells of the brain and spinal cord. They make and secrete proteins called neurotrophic factors, which assist in the maintenance of nerve cells in the central nervous system. They also break down and remove proteins or chemicals that might be harmful to neurons (for example, glutamate, a neurotransmitter that in excess causes cells to become overexcited and die by a
Guidepost cells in the neural tube of Drosophilia available for the binding of growing axons. These studies have defined guidepost cells as non-continuous landmarks located on future paths of growing axons by providing high-affinity substrates to bind to for navigation. Guidepost cells are typically immature glial cells and neuron cells, that have yet to grown an axon. They can either be labeled as short range cells or axon dependent cells. To qualify as a guidepost cell, neurons hypothesized to be influenced by a guidance cell are examined during development. To test the guidance cell in question, neural axon growth and migration is