In vitro studies have shown that the cerebrospinal fluid of patients with multiple sclerosis transports compounds which may affect the function or viability of central nervous system cell function. The presence of nerve ion channel blockers and other molecules, as yet unidentified, which may cause the death of nerve cells or oligodendrocytes has been shown, although their relevance and clinical correlation is still not clear. If their usefulness is proved, these methods may be useful in the search for inhibitors of the noxious effects of the substances mentioned.