title: Nerve growth factor levels in mouse serum: variations due to stress.
abstract: The presence of nerve growth factor (NGF) in the serum of adult male mice was assayed using the chick embryo dorsal root ganglion (DRG) bioassay technique in a serum free N1 supplemented medium. Wide variations in the serum-induced nerve fiber outgrowth response were observed when serum was obtained from animals maintained four per cage. Of 64 mice tested, sera of 7 animals induced a profound nerve fiber outgrowth response while the sera of 57 mice failed to show a similar response. In animals kept in isolation for 7 days prior to the start of the experiment, aggression provoked a marked increase in serum NGF levels. In contrast to the sera of aggression-unprovoked mice, the sera of all aggression-provoked mice stimulated a dense nerve fiber outgrowth. The sera of both groups of mice stimulated an intense proliferation and migration of nonneuronal cells. The neurite outgrowth responses elicited by sera from aggression-provoked and unprovoked mice were completely inhibited by the rabbit anti-NGF antiserum. In conclusion, both crowded housing and aggression in mice may provoke an elevation in the serum NGF levels that can be confirmed by the ganglion bioassay technique.
mesh_terms: D000374:Aggression / Q000502:physiology; D000818:Animals; D001681:Biological Assay; D003441:Crowding / Q000502:physiology; D008297:Male; D051379:Mice; D009414:Nerve Growth Factors / Q000097:blood*; D013312:Stress, Physiological / Q000097:blood*
chemical_list: D009414:Nerve Growth Factors