卡那霉素 B

Bekanamycin (Kanamycin B) is a precursor for semisynthetic antibiotics such as Arbekacin and Dibekacin and is generally extracted from the broth of S. kanamyceticus .
Bekanamycin (Kanamycin B) in a concentration-dependent fashion reduces reversibly the quantal content of the end-plate potentials while it has no observable effect on the configuration of the extracellularly recorded presynaptic action potential. The reduction in evoked transmitter release produced by Bekanamycin could be antagonized either by increasing the external calcium concentration or by drugs like the aminopyridines which are to greatly enhance transmitter release from motor nerve terminals. Bekanamycin exerts potent inhibitory effects on transmitter release probably by interfering with the influx of calcium that occurs during depolarization of motor nerve terminals.