Distribution of D1-like and D2-like dopamine receptors in the brain of genetic epileptic WAG/Rij rats.

The densities of the dopamine (DA) D1-like and D2-like receptors were studied by autoradiography in brain regions of rats with (WAG/Rij strain) and without (ACI strain) genetic absence epilepsy. The core of the nucleus accumbens in WAG/Rij rats had a lower density of D1-like receptors than in ACI rats, a reduction of both D1-like and D2-like DA receptors was also found for the dorsal striatum (dorsal caudate-putamen). On the other hand, the density of D2-like receptors was higher in cortical (frontal and parietal) regions and lower in the CA3 region of the hippocampus of WAG/Rij, as compared to ACI rats. These results give new information about possible malfunction of the brain dopaminergic system in the WAG/Rij rat model of absence epilepsy. It seems that there are differences between WAG/Rij and other models of absence epilepsy, especially concerning the role of striatum.