Dopamine receptors in the striatum and limbic system of various strains of mice: relation to differences in responses to apomorphine.

Dopamine receptors, defined as [3H]spiroperidol binding sites, had similar population parameters in the limbic forebrain of C57BL/6, Albino Swiss and DBA/2 mice, but the parameters of the striatal populations were different: not only the densities differed among themselves, but the KD value of the striatal dopamine receptors of DBA/2 mice was significantly higher than that in the two remaining strains. Behavioral responses of Albino Swiss mice to apomorphine: biphasic effect of apomorphine on locomotor activity and stereotypy characterized by high motility, frequent rearing and sharp, not very frequent bites, were similar to those described earlier for C57BL/6 mice, and differed from those reported for DBA/2 mice. The results suggest that the difference in responding to apomorphine in various strains of mice may be related to differences in their striatal dopamine receptors.