THE EFFECTS OF SODIUM SELENITE ON VENTRAL ROOT REFLEXS IN THE ISOLATED TOAD SPINAL CORD / 西安交通大学学报(医学版)

ABSTRACT

The effects of sodium selenite on ventral root reflexs in the isolated spinal cord of the toad were investigated. It was found that the effects of selenite on ventral root reflexs were excited first and then inhibited gradually. Using sucrose gap technique, we have found that selenite produced a significant depolarization on the rentral roots. Mg~(2+)ion markedly reduced this effect, which indicated that selenite had an importment action on interneurons activities of the spinal cord. Sodium selenite could antagonized the post-tetanus hyperpolarization of the ventral roots, which gave another evidenoe for proving its depolarization. The data described above suggest that the actions of sodium selenite on toad spinal cord are exciting first and then inhibiting gradually.