DISTRIBUTION OF CHOLECYSTOKININ IMMUNOREACTIVITY IN THE BALB C MOUSE FOREBRAIN - AN IMMUNOCYTOCHEMICAL STUDY/

The present study describes cholecystokinin (CCK) immunoreactivity (CC K-IR) distribution in the brains of control and colchicine-treated mic e. In the brains of control mice, the CCK-IR strongly revealed numerou s axons and terminals. Perikarya exhibiting a faint to moderate immuno reactivity were also observed in areas such as cortices, hippocampus, amygdala, septum, and thalamus. The colchicine treatment did not seem to notably affect the brain CCK-IR innervation, but resulted in profou nd changes of the perikaryal staining. Indeed, the regions, which cont ained numerous moderately stained perikarya in the control animals, ex hibited after colchicine treatment immunoreactive perikarya intensely stained but only in moderate number. This feature obviously appeared i n the cortex in which, in addition to strongly stained perikarya, colc hicine induced the appearance of numerous CCK-IR hillocks. In the late ral amygdala and thalamus of colchicine-treated animals, the somatic i mmunoreactivity was considerably decreased. The regions, such as parav entricular hypothalamic nucleus and bed nucleus of the stria terminali s, which in the control animals did not exhibit any stained perikaryon , showed a high number of strongly stained cell bodies after colchicin e treatment. This study, mapping the mouse forebrain CCK-IR, demonstra ted a wide distribution of this peptide. Moreover, CCK-IR is spontaneo usly visible in neurons of untreated mouse in some brain areas previou sly shown in the rat to exhibit CCK mRNA, but no clear perikaryal CCK- IR even after colchicine treatment. (C) 1997 Elsevier Science B.V.