ABSTRACT
Data obtained in experiments carried out over more than 20 years in our laboratory suggest a significant role for the brain serotonergic system. A particular interest in the brain neurotransmitter serotonin arose from data indicating the involvement of the serotonergic system in regulation of both catalepsy (Kostowsky et al., 1972) and some types of aggressive behavior (Lagerspetz and Lagerspetz, 1974; Popova et al., 1978). Two main methodological approaches were used: 1) In order to elucidate the genetic correlations between brain serotonin metabolism and the predisposition to freezing, a number of inbred mouse strains were studied. 2) Two different rat strains were studied, selectively bred at the Institute of Cytology and Genetics, Novosibirsk, for their predisposition to catalepsy, and for their lack of defensive aggression to man, as well as silver foxes bred for more than 30 years for nonaggressive behaviour.
