Study of biophysical properties of mechanosensitive channels in cultured dorsal root ganglion neurons of neonatal rats / 中华物理医学与康复杂志

ABSTRACT

Objective To investigate the biophysical properties of mechanosensitive(MS) channels in cultured dorsal root ganglion neurons of neonatal rats. Methods MS channels current of cultured dorsal root ganglion neurons of neonatal rats were recorded using cell-attached and inside-out patch-clamp technique.The biophysical properties such as pressure response relationship,current voltage relationship,channel kinetics and ion selectivity were analyzed.Membrane stretch was achieved by the application of negative pressure(suction) to a patch-clamp electrode. Results One type of MS non-selective cation ion channels in the membrane patches tested in cultured dorsal root ganglion neurons of neonatal rats were recorded. Those channels were activated rapidly when suction was applied, and kept active during sustained application of negative pressure and quickly turned off when the suction was released.The MS channels exhibited a nearly linear current voltage relationship in the balance solution.The outward chord conductance was (96.2?3.6)pS (mV is between +40 mV and +60 mV) and the inward slope conductance was (62.5?0.4)pS (mV is between -60 mV and 0 mV). This kind of channels appeared to be outward rectifier.The average reversal potential was (-2.3?0.8)mV.The channel kinetics analysis indicated that suction could significantly increase the duration of short-openings and long-openings and decrease that of long-closings,with no effects on short-closings. Conclusion The results of this study could serve as a reference to the understanding of electric activity of DRG neurons.