Cook T M, Crutcher K A
Department of Anatomy, University of Utah School of Medicine, Salt Lake City 84132.
Exp Brain Res. 1988;70(2):433-6. doi: 10.1007/BF00248368.
The developmental pattern of hippocampal mossy fiber (dentate granule cell axon) innervation to the pyramidal cell layer was examined with anterograde transport methods. Injection of 3H-leucine into the dentate gyrus on PN 1 resulted in labeling of the incipient stratum lucidum extending to, but not beyond, the CA3 region on PN 3 and 5. Since destruction of CA3 pyramidal cells on PN 5 results in aberrant mossy fiber innervation to CA1 pyramidal cells (Cook and Crutcher 1985), these results suggest that the presence of mossy fibers in CA1 of the rat represents a neoinnervation (perhaps representing a more primitive pattern of connectivity) and not the persistence of a transient developmental projection.
