Increased concentrations of uric acid in the spinal cord of rats with chronic relapsing experimental allergic encephalomyelitis.

We investigated the effects of chronic relapsing experimental allergic encephalomyelitis (first attack and first recovery) on uric acid (UR) concentrations in Lewis rat spinal cord. Perchloric extracts of 9 regions between spinal cord segments C3 and Co1 were injected into a reversed-phase high-performance liquid chromatographic system, and UR was quantified electrochemically. In all regions UR, which was lower than 0.5 micrograms/g wet tissue in rats injected with adjuvant (controls), increased to a variable extent during the attack (5-12 micrograms/g, maximum in T11-L2) and returned during recovery to a residual level of 1-2 micrograms/g. These findings can be partly attributed to blood-brain barrier damage.