FK506 TO PREVENT BRAIN CELL DEATH

- Researchers at the Fujisawa Institute of Neuroscience at the University of Edinburgh, UK, have found that Fujisawa's immunosupressant, FK506 (tacrolimus), can substantially reduce the death of brain cells resulting in brain damage if administered up to an hour after a stroke. The researchers say the drug's mechanism of action is suspected to be in preventing the activation of the enzyme calcineurin, although the role of the enzyme in neurodegeneration is still unclear. However, they also postulate that the pathway could involve reducing nitric oxide production from the calcineurin-mediated dephosphorylation of nitric oxide synthase. Nitric oxide is proposed to mediate the neurotoxic properties of excitory amino acids and NO donors.