TABLE 2.
Morphometric Measurements of Zebrafish Maxillary Barbel Axons1
| No. myelinated, unmyelinated axons (total axons, % myelinated) |
Myelin. axon area, μm2 (median, range) |
Unmyel. axon area, μm2 (median, range) |
Myelin thickness, μm (median, range) |
g-ratio (median, range) |
|
|---|---|---|---|---|---|
| Normal barbel | |||||
| 1 | 80, 42 (122, 65.5) | 0.78, 0.11–3.30 | 0.29, 0.08–0.99 | 0.11, 0.04–0.24 | 0.83, 0.60–0.91 |
| 2 | 95, 59 (154, 61.7) | 0.94, 0.25–6.44 | 0.31, 0.04–2.07 | 0.14, 0.06–0.33 | 0.80, 0.65–0.91 |
| 3 | 141, 82 (223, 63.2) | 0.55, 0.14–3.00 | 0.12, 0.02–1.83 | 0.13, 0.03–0.49 | 0.75, 0.55–0.90 |
| Regenerated barbel | |||||
| 1 | 82, 42 (124, 66.0) | 0.81, 0.14–4.93 | 0.40, 0.10–1.50 | 0.11, 0.03–0.22 | 0.81, 0.57–0.95 |
| 2 | 122, 65 (187, 65.2) | 0.79, 0.09–2.60 | 0.26, 0.02–2.11 | 0.11, 0.04–0.30 | 0.82, 0.63–0.96 |
| 3 | 102, 70 (172, 59.3) | 0.72, 0.15–3.10 | 0.17, 0.02–0.89 | 0.09, 0.06–0.16 | 0.84, 0.69–0.90 |
| All normal (n = 3) | 316, 183 (63.4) | 0.72, 0.11–6.44 | 0.22, 0.02–2.07 | 0.13, 0.03–0.49 | 0.79, 0.55–0.91 |
| All regenerated (n = 3) | 306, 177 (63.3) | 0.75, 0.09–4.93 | 0.27, 0.02–2.11 | 0.11, 0.03–0.30 | 0.83, 0.57–0.96 |
1
Fiber type, axon cross-sectional area, and myelin thickness were measured from transmission electron micrographs of normal (n = 3) and 28 days postsurgery regenerating tissue (n = 3). All fish were 6-12 months old of a wild-type “AB” strain. g-ratio calculations are described in Materials and Methods.