Glial cell line-derived neurotrophic factor and is the first member of the GDNF family of ligands (GFL) found. Glial cell line-derived neurotrophic factor has been shown to interact with GFRA2 and GDNF family receptor alpha 1. GDNF has regenerative properties for brain cells and showed potential as treatment for Parkinson's disease - monkeys with an induced form of Parkinson's disease showed less trembling when treated with the drug, and neuronal fibres grew in part of the human brain exposed to the drug. However progress to a treatment is hampered by the problem of delivering the drug to brain cells through the blood-brain barrier in human.
Human body and about 23 litres of fluid inside cells. The content, acidity and composition of the water inside and outside cells is carefully maintained. The main electrolytes in body water outside cells are sodium and chloride, whereas within cells it is potassium and other phosphates. The body contains trillions of cells, the fundamental unit of life. At maturity, there are roughly 30–37 trillion cells in the body, an estimate arrived at by totalling the cell numbers of all the organs of the body and cell types. The body is also host to about the same number of non-human cells as well