Fig. 2

Retrograde degeneration of DAergic axons in the MFB. a, b Normal DAergic thick axons and astrocytic processes of the MFB. c A thick degenerating axon surrounded by astrocytic processes. d Three spheroids produced by fracture of a degenerating axon (TH in green) and which were penetrated by an astrocytic process (cyan). e Mean ± standard error of fluorescence values under the white lines shown in d. f, g A spheroid penetrated by an astrocytic process (slice through which the astrocytic process passed is shown in h). i A spheroid penetrated by two astrocytic processes. j A slice of the spheroid in i. k The mean ± standard error of white lines shown in j. l, m A spheroid surrounded by an astrocytic process. n, o A spheroid near the cell somata of an astrocyte and surrounded by two astrocytic processes of this cell. p A spheroid (top-right) and distant microglial cells (bottom-left). q A microglial cell with projections near a spheroid. r A slice of a spheroid with nearby small processes of a microglial cell