Nerve growth factor improves evoked potentials and long-term potentiation in the dentate gyrus of presenile rats

Chronic infusion of nerve growth factor (NGF, 1.2 mu g/day) for 14 days to presenile rats (17 months at the beginning of treatment) that showed an initial cognitive impairment led to an improved long-term potentiation in the dentate gyrus. Both the relative increase of the slope of the population excitatory postsynaptic potential and that of the population spike were enhanced by NGF pretreatment after long-term potentiation induction at 400 Hz. The treatment was also able to increase the diminished baseline amplitude of the population spike, an effect not seen when the treatment was applied to older animals [Bergado, J., Femandez, C.I., Gomez-Soria, A., Gonzalez, O., 1997a. Chronic intraventricular infusion with NGF improves LTP in old cognitively-impaired rats. Brain Res. 770, 1-9] stressing the importance of an early start of trophic therapy to achieve better results. (C) 1998 Elsevier Science B.V.