[3H]Ro5-4864 benzodiazepine binding in the kainate lesioned striatum and Huntington's diseased basal ganglia

[3H]Ro5-4864-labeled peripheral-type benzodiazepine binding sites in the brain were studied after kainic acid lesions of the rat striatum. Following intrastrial kainate injections [3H]Ro5-4864 binding increased to approximately 1000% of control over a period of 1 week and was maintained at this level for up to 6 weeks. Two weeks after lesioning the number of binding sites (Bmax) was selectively increased while the dissociation constant (Kd) was only minimally affected. [3H]Ro5-4864 binding in the Huntington's diseased (HD) basal ganglia was not changed as compared to non-neurological control in the caudate nucleus and globus pallidus. A highly significant 51% increase was found in the HD putamen. It is concluded that the peripheral-type, Ro5-4864-sensitive benzodiazepine receptor in the brain may be predominantly localized on glial elements