Figure 1.

Iodine deficiency and hypothyroidism damaged nerve fibers in CA1 region. Silver staining was used to assess the damages of nerve fibers in CA1 region on PN14, PN21, PN28, and PN42 (n = 5). ID: Iodine-deficient group. On PN14, PN21, and PN28, cell bodies were arranged in order in each group, and fewer nerve fibers were observed. No markedly differences were observed between the control and the treatment groups. On PN42, nerve fibers (labeled with arrows) degeneration became apparent between the groups. Nerve fibers in iodine-deficient (Figure 1n), 5 ppm PTU-treated (Figure 1o), and 15 ppm PTU-treated (Figure 1p) groups were arranged in disorder, distorted, or disrupted, while nerve fibers in the controls were arranged in order with no obvious pathological changes (Figure 1m). Meanwhile, more nerve fibers were observed in the controls than the treatment groups. Scale bar represents 10 μm at lower left in (a) and applies to all panels.