Figure 7.

Subtle effect of heavy water on the myelin period. (a, c) X-ray diffraction patterns collected from mouse (a) sciatic nerves and (c) spinal cord segments equilibrated against either H₂O-saline or D₂O-saline. Scattering intensity is plotted against both the scattering vector q (Å⁻¹) and the reciprocal coordinate R (Å⁻¹). For clarity, the spectra have been offset along the y axis. For comparison, the dashed lines represent the average positions of the fifth-order and fourth-order reflection from sciatic nerves and spinal cords, respectively, in H₂O-saline. (b, d) Scatter plots of relative amount of myelin [M/(M + B)] versus myelin period d for mouse sciatic nerves (b) and spinal cords (d) equilibrated against either H₂O-saline or D₂O-saline. Error bars represent ±1 standard deviation centred on the average for each group. Statistical significance was calculated using a paired t-test on parameters measured from single sciatic nerves or averaged parameters from two segments of spinal cord isolated from each mouse (n = 3) split between each of the two treatments.