Table 2: Projection patterns of facial motoneurons. Number of motoneurons with axons in the zygomatic, buccal, or marginal mandibular branches of the facial nerve of intact rats (Group 1: Intact), in rats after transection of the right facial nerve followed by entubulation with collagen only (Group 2: Collagen), with collagen plus naive SC's (Group 3: Collagen+SC's), or with collagen plus genetically modified SC's (groups 4 and 5). In groups 6–9 entubulations were followed by manual mechanical stimulation (MS) of the vibrissal muscles.

Group of animalsNeurons projecting only into the zygomatic nerve (Dil-only)Neurons projecting into the zygomatic and buccal nerves (Dil+FG)Neurons projecting into the zygomatic and marginal mandibular nerves (Dil+FB)All Dil labeled neurons projecting into the zygomatic nerve (Dil, DiI+FG, DiI+FB)Neurons projecting only into the buccal nerve (FG-only)Neurons projecting only into the marginal mandibular nerve (FB-only) Total number of neurons projecting into zygomatic buccal and marginal mandibular nerves (Dil-only, FG-only, FB-only)

(1) Intact SD rats291 ± 35291± 351406 ± 214349 ± 782046 ± 327
100%0%0%100%
(2) Collagen only323 ± 67202 ± 58*161 ± 60*696 ±192*2387 ± 256*1976 ± 243*5059 ± 691*
46%29%25%100%
(3) Collagen + naïve Schwann cells (SC's)372 ± 88174 ± 66*138 ± 73*684 ± 215*2040 ± 443*1754 ± 509*4478 ± 1167*
54%25%21%100%
(4) Collagen + SC-FGF- 234 ± 68130 ± 54*83 ± 41*447±162*2062 ± 296*1883 ± 184*4392 ± 642*
52%29%19%100%
(5) Collagen + SC-FGF- 269 ± 115151 ± 70*110 ± 52*532 ± 232*2304 ± 363*1918 ± 334*4754 ± 929*
50%28%22%100%
(6) Collagen only + MS322 ± 68184 ± 86*128 ± 43*634 ± 197*2243 ± 423*1784 ± 523*4670 ± 1143*
51%29%20%100%
(7) Collagen + naïve SC's + MS321 ± 87186 ± 36*168 ± 78*675 ± 201*2190 ± 543*1752 ± 309*4617 ± 1053*
48%28%24%100%
(8) Collagen + SC-FGF- + MS252 ± 91330 ± 93*177 ± 45*759 ± 229*2215 ± 204*1965 ± 492*4939 ± 925*
33%43%24%100%
(9) Collagen + SC-FGF-  + MS303 ± 69333 ± 96*195 ± 48*831 ± 213*2280 ± 306*1899 ± 723*5010 ± 1242*
36%40%24%100%

*Significant differences of group mean values (ANOVA and post-hoc Tukey's test, ) from intact rats.