Effects Of Sodium Metabisulfite On Ion Channels In Rat Dorsal Root Ganglion Neurons

Sodium metabisulfite (SMB) is most commonly used as a preservative in food products, like as biscuit, chocolate, jam, sausage, salami, in many alcoholic liquor like as beer, wine, champagne etc, and in drugs such as parenteral amino acid solutions. SMB has cytotoxic and genotoxic effects. SMB can induce bronchoconstriction in asthmatic patients. Recent studies have reported that SMB can induce the CAs and the SCEs in human lymphocytes. SMB also might have neurotoxicity. Dorsal root ganglion (DRG) neurons are primary sensory neurons and transmit sensory information from peripheral regions to the central nervous system. DRG neuron plays a important role in regulating systemic activity. So we studied the effects of SMB on ion channels using the whole cell configuration of patch-clamp technique in acutely isolated DRG neurons. The results are follows:SMB increased the amplitudes of transient outward potassium currents (TOCs) and delayed rectifier potassium current (I_K) in a concentration- and voltage-dependent manner. Ten μM SMB did not affect the activation process of TOCs and shifted the steady-state activation curve of I_K in the hyperpolarizing direction. SMB inhibited their inactivation process of TOCs. SMB also increased the amplitudes of TTX-S and TTX-R sodium currents in...