Measurement of Ion Diffusivity in Intervertebral Disc Using a Two-Point Electrical Conductivity Approach

摘要

The intervertebral disc (IVD) is an avascular structure, relying on diffusion for cellular nutrition. Therefore, understanding transport in IVD tissue is important for elucidating mechanisms and pathways of nutritional supply to the disc. Here, a new two-point electrical conductivity approach to measuring the diffusivity of ions in IVD tissues was developed. In order to test the reliability of this method, the Cf ion diffusivity in bovine annulus fibrosus (AF) and nucleus pulposus (NP) tissues was determined. For AF, the CI~- ion diffusivity was measured as 7.56 ± 2.12 × 10~(-10) m~2 /sec (n=15), while that in NP was 1.03 ± 0.16 × 10~(-9) m~2/sec (n=15). Results found here are in agreement with those in the literature for ion diffusion in IVD tissues, indicating this new method can reliably measure ion diffusivity in IVD tissues.