| [ Summary ] |
The middle molecular (MM) hypothesis, in which neurotoxins were considered to exist in the MM range and increased removal of MM, which was considered to be obtained by increased values for dialysis time multiplied by membrane area (m2), was reported by Babb et al. in 1971. A particular toxic substance has never been identified, although MM toxins have been investigated by many researchers. Toxic MM substances, which are synthesized, metabolized and accumulated in the cells, may accumulate in uremic patients. Although low molecular weight proteins (LMWP), such as Beta2-microglobulin, are higher in molecular weight than MM, they exist mainly in extracel lular spaces. Increased removal of MMs and LMWPs requires hemodiafiltration with high ly permeable hemofilters and long hours of treatment. MM removal may be more difficult than that for LMWP, because MMs exist not only in extracellular spaces but in intracellular spaces. |