TAURINE AND COBALT INDUCED EPILEPSY IN THE RAT: A BIOCHEMICAL AND ELECTROCORTICOGRAPHIC STUDY

Abstract– The level of taurine around the epileptic focus induced by cobalt-gelatine pellet implantation into rat brain was found to be reduced at 8-11 days post-operation, the time of maximal spike activity in the electrocorticogram. It returned towards normal at later times. This pattern was seen not only in the primary focus, but also to a lesser extent in the secondary focus in the contralateral cortex. Acute administration of taurine intraperitoneally or intraventricularly resulted in at most transient effects on epileptic spiking.
Chronic oral taurine elevated brain taurine in normal rats only after prolonged administration, but in cobalt-treated rats it prevented the fall of taurine in the secondary focus, and reduced the extent and duration of the fall in the primary focus; nonetheless chronic oral or intraventricular administration failed to modify the development of spike activity. At 11 days after implantation, chronic oral taurine did not significantly reverse the falls in transmitter amino acids in the primary focus. It is concluded that taurine is ineffective in altering the development or expression of this type of cobalt-induced epilepsy in the rat, in spite of adequate penetration to the brain. Possible reasons for the discrepancies with studies by other workers are discussed.