FIGURE 1.

Comparison of short- and long-term MGE cell morphology with cortical and spinal cord neurons from GAD-GFP transgenic mice. (a) At the level of the injection site, MGE-derived, GFP-immunoreactive cell bodies and processes are densely distributed throughout the dorsal horn (DH) 6 weeks post-transplantation. SG, substantia gelatinosa; wm, white matter. (b) Morphology of the MGE cells that migrated from the injection site is readily appreciated. They have small round or oval cell bodies with many fine dendrites, which are characteristics of cortical (Ctx) GABAergic interneurons (g & h). (c–f) Five months after transplantation, the MGE cells retain their cortical morphology. Arrowheads point to cell bodies of MGE neurons. Arrow F in E points to a cell shown at higher magnification in F. (g–l) Compared to cortical GAD-GFP neurons from transgenic GAD-GFP mice (g & h), those in deeper dorsal horn (i & j) are generally multipolar with a few primary dendrites that radiate circumferentially. Longitudinal sections (k & l) revealed that transgenic GAD-GFP neurons in the SG have a characteristic islet cell morphology, with fusiform cell bodies and rostrocaudally oriented dendrites. Scale bars: 100 μm in (a) and (c); 50 μm in (b), (d-f); 25 μm in (g-l)