Lateralization of neocortical dopamine receptors and dopamine level in normal Wistar rats.

A lateral asymmetry of dopamine receptors (D-1, D-2) and dopamine (DA) level was found in the left and right neocortices of male Wistar rats. The specific D-1 receptor binding (3H-SCH 23390) was by 24% (p less than 0.05), the specific D-2 receptor binding (3H-spiperone)----by 31% (0.1 greater than p greater than 0.05) and the DA level ---- by 80% higher (p less than 0.001) in the right than in the left neocortex. In the other examined brain regions (striatum and limbic system) no lateralization in D-1 or D-2 receptors was observed. The physiological significance of the neocortical lateralization (DA receptors and level) is unknown, yet it is important for experimental and methodological reasons.