Table 1.

Functional contacts with somatic membrane (percentage of surface)

P0P1P2P3P4
Postsynaptic density0.31 ± 0.3%0.28 ± 0.3% (0.9-fold)1.28 ± 0.8% (4.1-fold)3.50 ± 2.0% (11.3-fold)4.83 ± 0.4% (15.6-fold)
Punctum adherens0.04 ± 0.02%0.12 ± 0.1% (3-fold)0.60 ± 0.3% (15-fold)0.96 ± 0.4% (24-fold)2.93 ± 0.4% (73-fold)
Number of MNTB regions measuredan = 4 (12)n = 4 (24)n = 4 (7)n = 5 (11)n = 4 (16)
  • Data are mean ± SD.

  • aValues in parentheses reflect the number of cells with complete perimeters measured across serial sections at each age. Somatic membranes of additional cells were partly included in the measurement field and are included in this analysis. The MNTB was divided into four (or five at P3) equal regions oriented from medial to lateral. Measurements for each complete or partial cell were placed into the appropriate region and combined as a single measurement for that region. Therefore, means and SDs are based on the number of regions analyzed at each age.