Cell migration from the corticostriatal angle to the basal telencephalon in rat embryos

Lateral cortical stream (LCS) has been described as a flow of cell migratio n found in the lateral cortex of the embryonic telencephalon of mammals. Th e destinations of the cell migration were reported as the ventrolateral neo cortex, the pyriform cortex, endopyriform nucleus and the claustrum. At the same time, however, other destinations of LCS have been suggested in the v entral telencephalon. Therefore, we investigated the additional destination s of the LCS using a combination of several molecular biological techniques . Using an expression vector of modified green fluorescent protein (GFP) in troduced into the ventricular zone (VZ) around the corticostriatal angle, b oth tangential and radial cell migration was revealed in the LCS. The radia l cell migration in the LCS supplied cells to the ventro-lateral neocortex, pyriform cortex and to the level of the lateral olfactory tract, in the se cond experiment, we injected COS-1 cells transfected with a Sema3A expressi on vector into one side of the neocortex. The cell supply to the destinatio n of the LCS ceased due to the formation of a large necrosis in the LCS, wh ich was triggered by the Sema3A-COS cell injection, and the dense cell laye r in the olfactory tubercle shrunk on the side where COS cells were injecte d. These data indicated that the majority of neurons in the dense cell laye r of the olfactory tubercle reached this point through the LCS. One of the origins of the cells in the LCS would be in the corticostriatal angle. Neur oReport 12:775-780 (C) 2001 Lippincott Williams & Wilkins.