Striatal mechanism of action of corticoliberin on behavior in dogs in conditions of dopamine deficiency

This report describes studies of the interaction of the integrative dopaminergic and corticoliberin systems in the neostriatum during performance of situational food-related conditioned reflexes. Studies were performed in dogs with chemotrodes implanted in the substantia nigra and the head of the caudate nucleus. 6-Hydroxydopamine was injected into the substantia nigra at a dose of 50 μg, and 10 μg of corticoliberin was injected into the caudate nucleus. Blood cortisol and catecholamine levels were determined. Analysis of the result showed that an interaction takes place in the neostriatum between the corticoliberin and dopaminergic systems, and that in conditions in which dopaminergic structures are excluded, the efficacy of corticoliberin in the performance of behavioral acts decreases by 30–40%, i.e., complete expression of its regulatory role of motor situational conditioned reflexes is lost. Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 84, No. 8, pp. 728–734, August, 1998.