ABSTRACT
Aim To investigate the inhibitory effects of the novel compounds YZG-330 and YZG-331 in central nervous system. Methods The sedative effect was investigated by recording the spontaneous locomotor ac-tivity in mice. The hypnotic effect was evaluated by the latency and duration of the loss of righting reflex ( LORR) in the threshold dosage of sodium pentobarbi-tal treated mice. The two compounds induced the mice that had woken up after a threshold dosage pentobarbi-tal sodium to fall asleep again. The levels of GABA and Glu in brain were measured by HPLC-ECD. Re-sults The results showed that spontaneous locomotor activities decreased in YZG-330 (0.125, 0.5,2 mg·kg-1 ) treated mice and YZG-331 (1.25, 5, 20 mg· kg-1 ) treated mice. YZGs could extend the duration of the loss of righting reflex in threshold dosage of sodium pentobarbital treated mice, and significantly shorten sleep latency. YZGs were able to allow the mice that had woken up after a threshold dosage pentobarbital so-dium to fall asleep again. YZG-331 (40 mg·kg-1 ,i. g. ) could significantly increase GABA level in hypo-thalamus and cerebral cortex. The content of GABA had no significant change after YZG-330 ( 2 mg · kg-1 , ig. ) administration. Conclusions YZG-330 and YZG-331 have potent sedative and hypnotic effects. The efficacy of YZG-330 is stronger than that of YZG-331 , but the mechanism of two compounds sounds different.
ABSTRACT
Aim To investigate the sedative and hyp-notic effects of a novel compound H057 . Methods The sedative activity of H057 was investigated by re-cording the spontaneous locomotor activity in mice. The hypnotic property was evaluated by the latency and duration of loss of righting reflex( LORR) in mice and effect of H057 on the sleep onset in subthreshold dos-age of sodium pentobarbital treated mice. The extracel-lular levels of GABA and monoamine neurotransmitters in in cerebral cortex were measured by microdialysis in vivo. Results The spontaneous locomotor activity was decreased by 25% and 66% in H057 ( 5 , 25 mg · kg-1 ,i. p. ) treated mice, respectively. H057 ( 3, 5 mg·kg-1 ,i. p. ) increased the sleep onset to 62. 5%and 87. 5% in subthreshold dosage of sodium pentobar-bital(25 mg·kg-1,i. p. ) treated mice. H057(≥60 mg· kg-1 , i. p. ) could completely induce LORR in mice. The latency of LORR at dose of 60 mg · kg-1 was (24 ± 11) min and the duration of LORR was (96 ± 15 ) min. In vivo mircodialysis revealed that H057 (25 mg·kg-1 , i. p. ) could significantly increase the GABA level by 26% and decrease the 5-HT and NE levels by 50% and 38% in cerebral cortex in mice. Conclusion H057 has potent sedative and hypnotic effects, which may be closely related to the increased content of GABA and the decreased contents of 5-HT and NE in the extracellular fluid in cerebral cortex.