Nerve growth factor promoter driven neurotrophin-3 overexpression in the mouse and the protective effect of transgene on age-related behavioral deficits.

To clarify the biological function of neurotrophin-3 (NT-3) at the postnatal stage, we created a line of transgenic mice overexpressing NT-3 under the control of the mouse nerve growth factor gene promoter. Transgenic mice showed high-level NT-3 expression in the hippocampus and several tissues. We performed behavioral tests in young-adult (7-months-old) and aged (25-months-old) mice. Although aged non-transgenic mice exhibited spatial learning impairments in the Morris water maze, overexpression of NT-3 protected against these age-dependent spatial learning impairments in mice.