(A) Activity-dependent eCB release inhibits neurotransmitter release from synapses of both pyramidal cells (Pyr) and cholecystokinin (CCK)+ interneurons [2]. (B) Wnt signaling has been implicated in the control of presynaptic assembly and neurotransmitter release at excitatory afferents [4,48]. (C) Dendritic release of glutamate provides negative feed-back at perisomatic terminals of parvalbumin (PV)+ basket cells [7]. (D) In contrast, dendritic BDNF release enhances the efficacy of synaptic communication at select cortical synapses [5,24]. Abbreviations: 2-AG, 2-arachidonoylglycerol; AMPAR, AMPA receptor; CB1R, CB1 cannabinoid receptor; DAGLα/β, sn-1-diacylglycerol lipase α/β isoforms; Dvl, dishevelled; Fz, frizzled; GABAAR, GABAA receptor; Glu, glutamate; Gln, glutamine; Glase, glutaminase; GSK-3β, glycogen synthase kinase-3β; LRP, low-density lipoprotein receptor; mGluR, metabotropic glutamate receptor; NMDAR, N-methyl-D-aspartate receptor; PLC(β), phospholipase C (β isoform); SATs, system A amino acid transporters; TrkB, tyrosine kinase B receptor; VDCC, voltage-dependent Ca2+ channel; Wnt, Wingless-Int family of ligands.