Journal of Neuroscience, Vol 4, 1289-1299, Copyright © 1984 by Society for Neuroscience
Distribution, origin, and fine structures of cholecystokinin-8-like immunoreactive terminals in the nucleus ventromedialis hypothalami of the rat
S Inagaki, Y Shiotani, M Yamano, S Shiosaka, H Takagi, K Tateishi, E Hashimura, T Hamaoka and M Tohyama
The distribution, origin, and fine structures of cholecystokinin-8-like
immunoreactive ( CCKI ) fibers in the nucleus ventromedialis hypothalami
(vm) of the rat were examined using immunohistochemistry. CCKI fibers were
moderately concentrated in the ventrolateral part of the vm, decreasing in
number dorsomedially. However, no CCKI cells were seen in the vm even in
colchicine-treated rats. In addition, the destruction of the lateral part
of the nucleus parabrachialis dorsalis (pbd) where numerous CCKI cells were
seen resulted in a marked decrease in CCKI fibers in the vm on the operated
side. Electron microscopic observations revealed that CCKI terminals make
synaptic contact with soma, spine, and the proximal segment of the
dendrite. The neurons making synaptic contact with the CCKI fibers had
moderately electron- lucent cytoplasm. These findings suggest that the CCKI
fibers in the vm originate from CCKI cells in the lateral part of the pbd
and directly influence the vm neurons.