Relationship of centrifugal fibres to 'supporting' cells.

We have described cholinergic fibres which cross the tunnel to three levels of the cells on the opposite side--from the level of the efferent network to the base of a plaque at the level of the nucleus of the first Deiters cell. These fibres are dependent upon the OCB being intact. The same is true for those fibres seen within the Hensen cell region. However, the cholinesterase-staining fine fibres travelling along the floor of the tunnel to the base of the plaque are independent of the integrity of the OCB.