Maternal separation and early social deprivation in Octodon degus: quantitative changes of nicotinamide adenine dinucleotide phosphate-diaphorase-reactive neurons in the prefrontal cortex and nucleus accumbens. - Poeggel,G.; Lange,E.; Hase,C.; Metzger,M.; Gulyaeva,N.; Braun,K. (Neuroscience, 1999)