Modulation of AlCl_3 on GABA-activated currents in isolated rat DRG neurons / 中国药理学通报

ABSTRACT

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.