- Enhanced dendritic spine number of neurons of the prefrontal cortex, hippocampus, and nucleus accumbens in old rats after chronic donepezil administration. Alcantara-Gonzalez, F., Juarez, I., Solis, O., Martinez-Tellez, I., Camacho-Abrego, I., Masliah, E., Mena, R., Flores, G. Synapse (2010)