Nerve growth factor: enhanced recovery of feeding after hypothalamic damage.

A single intraventricular injection of nerve growth factor (NGF). given at the time of brain damage, facilitated the course of recovery from the lateral hypothalamic anorexic syndrome in male rats. In the second and third weeks after the trauma, NGF-treated rats ate more food, regained body weight more rapidly, and fed more vigorously in response to intraventricular administration of norepinephrine than untreated controls. After full recovery, rats that had been treated with NGF were resistant to reinstatement of the hypothalamic syndrome by 6-hydroxydopamine. NGF may facilitate behavioral recovery by promoting the development of supersensitivity to norepinephrine and possibly also by stimulating the growth of regenerating noradrenergic neurons in the brain.