抄録
O, S-Dicarbethoxythiamine (DCET) is one of the S-CAT's, which were synthesized by Takamizawa et al. (1) and found to be well absorbed through the intestinal tract in man as well as in experimental animals by Minesita et al. (2) at this Research Laboratory. It was confirmed that the toxic death by thiamine hydrochloride resulted from respiratory arrest following the blocking action in neuro-muscular transmission, while that by DCET resulted from cardiac arrest (3). Determination of DCET concentration in the blood, showed that these effects were not due to the thiamine converted from DCET but due to the DCET itself in the blood.
Both in the sciatic gastrocnemius preparation of cats and in the isolated toad sartorius muscle, thiamine blocked the neuro-muscular transmission as reported by other workers (3-7). While DCET potentiated the twitch tension of the sciatic gastrocnemius preparation of cats in situ. In the isolated toad sartorius muscle, however, it was recognized that the twitches by indirect stimulation were inhibited but the twitches by direct stimulation were much facilitated by the administration of DCET (3). So it is presumed that DCET has facilitating effects on the muscle twitching though it also has a blocking action in the neuro-muscular transmission similar to thiamine. In this experiment the facilitating effects of DCET on the striated muscle were reaffirmed and some of these facilitating mechanisms clarified.
DCET potentiates the twitch tension of striated muscle by facilitating the excitationcontraction coupling process in the muscle.
