Nerve growth factor influences neurobehavioral development of newborn mice.

Thirty-six male pups of the CD-1 outbred strain received from postnatal day 2 to day 10 a daily subcutaneous injection of either highly purified murine Nerve Growth Factor (NGF; 5 mg/kg), cytochrome c (5 mg/kg), or saline solution. NGF-treated pups showed a slight, but significant, reduction in body weight gain and a concomitant acceleration in the appearance of early signs of neurobehavioral maturation such as righting reflex, cliff aversion, and response to tactile stimulation of the perioral area. Other responses, including the ultrasonic vocalization pattern on day 7, were unaffected or affected to a lesser extent.