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AIM To study the modulation of AlCl 3 on GABA activated currents in isolated rat dorsal root ganglion (DRG) neurons. METHODS Using whole cell patch clamp technique to investigate the effects of AlCl 3 on GABA activated currents in isolated rat DRG neurons. RESULTS The majority of the neurons examined(46/58) were sensitive to GABA in the concentration range from 1 to 1 000 ?mol?L -1 . In the 46 GABA sensitive cells, responses induced by AlCl 3 manifested three types: (1) outward current(3/46); (2) inward current(5/46) and (3) no detectable response(38/46). As compared with GABA activated current, the amplitude of AlCl 3 activated current was smaller. Preapplication with low concentrations of AlCl 3 (≤100 ?mol?L -1 ), the GABA activated current in majority of the cells(32/38) was potentiated, which was dose dependent, the current in a few cells(4/38) was inhibited, while the remaining two(2/38) showed no effect. At higher concentration( 1 000 ?mol?L -1 ), AlCl 3 inhibited the GABA activated current( n =8). It was found that AlCl 3 potentiated both the peak value of and the steady state value of GABA activated currents. CONCLUSION AlCl 3 can modulate the function of GABA A receptors.
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Objective To explore the electrophysiological characteristics and the expression of mRNA and protein of L-type calcium channel in rat bone mesenchymal stem cells(MSCs). Methods MSCs were isolated,cultured and purified.RT-PCR was used to detect the mRNA expression of ?1C,?1D,?1H,?1S.The protein expression of L-type calcium channel(?1C) was testified by immunohistochamical.Ion currents were recorded in MSCs using whole-cell patch clamp technques.Results CD29,CD44,CD106 expressed in about 93% MSCs and CD14,CD34,CD45 expressed negatively.A high expression of mRNA in ?1C was detected by RT-PCR but no expressions were observed in ?1D,?1G,?1H,?1S.Immunofluorescent double labeling showed an expression of ?1C subunits in MSCs.Moreover,inward currents were recorded in 16 of 36 cells using whole-cell patch clamp techniques.The currents were activated around-30?mV and peaked at 0 to 10?mV and were blocked by nifedipine(10??mol/L).These cells had larger currents with Ba~(2+)(10?mmol/L) in bath solution than with Ca~(2+)(2?mmol/L).Conclusion The results indicated that adult rat MSCs expresse functional L-type calcium channels.It is possible that this channel plays a role on the proliferation and differentiation of MSCs.