Studies On The Nootropic Effect And Mechanism Of Action Of (-)-clausenamide And Comparison Of The Effects Of (-)-and (+)-clausenamide On The Synaptic Transmission In Hippocampus Of Rats

Learning and memory is an advanced function of brain, its exact mechanisms are not well-known up to date. Synapses are essential structures in the nervous system through which signals are transmitted among neurons and processed and integrated. Changes in the function and morphology of synapses are considered as the neurobiological basis of learning and memory. Since the discovery of long-term potentiation ( LTP ) of synaptic transmission in the rabbit hippocampal formation by Bliss et al. in 1973, the above hypothesis has been gradually accepted by more and more neuroscientists. (-)-Clausenamide showed obvious nootropic action in various behavioral test and its mechanisms have been studies in many espects, but less information about effects of ( - )-dausenamide on synaptic transmission exist now. The extracellular recording technique, biochemical and histochemical methods are employed in the present study to compare the effects of (- )-Clausenamide and ( + )-Clausenamide on the synaptic transmission in dentate gyrus of rats in vivo and to analyse their mechanisms of action. In addition, observation of the effect of aggregated β-AP ( 25-35 ) on the spatial learning and memory of rats with comparing the action of ( - )-Clausenamide and ( + )-Clausenamide is also included. The main results are as follows:1. Effects of (- )-Clausenamide and ( + )-Clausenamide on the spatial learning and memory impairment induced by β-AP ( 25-35) Results of the present study showed that, icv injection of aggregated form of β-AP ( 25-35 ) induced obvious learning and memory impairment of rats in Morris water maze training course two weeks after its delivery, although without affecting the response of rats in the one-way avoidance test —...