Effect Of P2X7Receptor Antagonist BBG On The Synaptic Growth Of The Rat Hippocampal Neuron And Cognitive Function In Alzheimer’s Disease

Objective1.To study the effect of P2X7receptor on the stage of synaptic developmentatinduced by soluble β-amyloid protein42oligomers，including the possible effect of Aβ42、BBGon the filopodia length density, the spine density and dendritic tree in cultured hippocampalneurons.2.To study the relative expression of P2X7receptor on the hippocampus of APP&PS1mice compared with normal mice, With the change of the AD pathological process,the possiblechange of the expression of P2X7receptor.3. To study the effect of P2X7receptor antagonist BBGon the sdudy and memory on mice.Methods1. Primary hippocampal neuronal cultures from postnatal1-day-old Wistar rats areprepared, and are cotransfected with farnesylated enhanced green fluorescent protein (F-GFP) andGFP-actin at the day5in vitro (DIV5) to display the morphological details of the dendrites anddendritic protrusions.Neurons are incubated with SO Aβ42for3hours in experimental groups atDIV7and DIV14. Identify the APP&PS1transgenic mice by PCR; Extract of the total RNA andreverse transcribe it into cDNA, detect the relative expression of P2X7receptor on hippocampaltissue by Real-time PCR.3.Inject Aβ42on the CA1of hippocampus by stereotaxictechnique,making the AD model, Intraperitoneal injection of BBG, Detect the sdudy,memory andthe influence of depression by behavioral experiments new object recognition test,forcedswimming test,Morris Water Maze.Results1. Incubation of DIV7hippocampal neurons with SO Aβ42alone for3h significantlydecrease the dendritic filopodia density. Pre-treatment with BBG for24h rescued the SO Aβ42-induced dendritic filopodi loss.Both the length and the motility of filopodia are not altered in thepresence of SO Aβ42alone or BBG treated with before SO Aβ42incubation. Incubation of DIV14hippocampal neurons with SO Aβ42alone significantly decrease the spines densiy,while BBGinhibited SO Aβ42-induced decrease of filopodia density at DIV14. In the hippocampus ofAPP&PS1transgenic mice,the relative expression of P2X7receptor show a trend of first rises thenfalls and there is no significant difference compared with normal mice along with the age in mice.BBG significantly improves the ability of study and memory of mice and have an certain effect onthe depression. Conclusions Treatment with SO Aβ42cause damage on the synaptic development,leading tothe decrease of filipodie density and spines density, Pre-treatment with BBG can rescue theimpairment of synaptic development induced by SO Aβ42, which may relate to P2X7receporthrough suppression expression. The Expression of P2X7receptor show a peak phenomenon in theprocess of AD pathology, P2X7receptors are involved in the pathological process of AD.