Abstract:

Abstract:Objective To observe the effect of pregnanolone(PGN) on  suprachiasmatic nucleus(SCN) neurons of rat brain slices,and analyze the  possible mechanism of central sedation and anesthesia effects of PGN. Methods PGN,GABA,and Bic were perfused into the rat brain slices,the extracellular discharge changes of SCN were recorded after perfusion with extracellular discharge record method.Results  After perfusion of PGN,the activity of  SCN neurons was inhibited,the inhibitory rate was (49.72±16.28)%;Co-application of PGN and GABA could enhance the inhibitory effect on SCN neurons,the inhibitory rate was (71.54±19.62)%，there was significant difference between them（P<0.05 ）;pre-application of GABA blockers Bic could block the effects of PGN,the inhibitory rate was (29.85± 6.20)%(P<0.05）.Conclusion PGN may directly affect the SCN neuron membrane excitability.Its role may be related to GABAA receptor on SCN neuron membrane.PGN can increase the combination of GABA and GABAA receptors to enhance the function of GABA.

Key words: pregnanolone； , suprachiasmatic nucleus； , unit discharges