多选题How do endocannabinoids influence synaptic strength?A、 They directly block the GABA receptor in the postsynaptic neuron.B、 They activate a G-protein-coupled receptor which blocks presynaptic Ca2+ channels.C、 They directly activate presynaptic Ca2+ channels.D、 They directly block the presynaptic Ca2+ channels.多选题How is LTD generated?A、 High frequency stimulationB、 Low frequency stimulationC、 Increase in intracellular Ca2+D、 Activation of CaMKII多选题What is the current known role of complexin in synaptic transmission?A、 Complexin makes sure vesicles are near Ca2+ channels.B、 Complexin binds vesicles to scaffolding proteins in the presynaptic membrane.C、 Complexin clamps the SNARE complex in an intermediate step prior to vesicle fusion.D、 Complexin is required for presynaptic Ca2+ channels to open.多选题When LTP is generated, ( ) will increase?A、 Pre-synaptic membrane potentialB、 Post-synaptic membrane potentialC、 Post-synaptic NMDAR densityD、 Pre-synaptic quantal size多选题How is LTP generated?A、 High frequency stimulationB、 Low frequency stimulationC、 Increase in intracellular Na+D、 Inactivation of CaMKII