The binding of [3H]SCH 23390 has been studied in various brain
regions of male mice with the experience of repeated victory
(winners) or defeat (losers) gained over 10 (T10) and 20 (T20)
days of daily agonistic confrontations. In the frontal cortex, Bmax
of [3H]SCH 23390 binding sites was found to be increased in T10
losers and decreased in T20 losers when compared to the control
mice. In the striatum, T10 and T20 winners had reduced values
of [3H]SCH 23390 binding sites than the ones in the control mice.
The Kd was increased in the frontal cortex of T10 losers and T10
winners as well as in the amygdala of T20 losers. Reduced Kd
values were found in the striatum of all experimental groups as
well as in the amygdala of T20 winners. Thus, both specific
changes relating to social behavior patterns and non-specific
ones in [3H]SCH 23390 binding were found in the brain regions
of mice after 10 and 20 days of intermale confrontations.