Comparisons of cocaine receptors in brain regions from WKY and SHR

Both high- and low-affinity sites for [3H]cocaine binding were present in the striatum, hippocampus, olfactory tubercle, and hypothalamus of WKY and SHR. In the striatum, Kd values of both sites and the Bmax value of the high-affinity site were lower in SHR than in WKY rats. In the hippocampus, only the Kd value of the high-affinity site was lower in SHR than in WKY rats. However, there were no differences in Kd or Bmax values between strains in the olfactory tubercle or hypothalamus. The differences in characteristics of [3H]cocaine binding in WKY and SHR may provide a neurochemical basis for the different responses of the two strains to cocaine administration.