title: Synaptic connectivity in hippocampal neuronal networks cultured on micropatterned surfaces.
abstract: Embryonic rat hippocampal neurons were grown on patterned silane surface in order to organize synapse formations in a controlled manner. The surface patterns were composed of trimethoxysilylpropyl-diethylenetriamine (DETA) lines separated by tridecafluoro-1,1,2,2-tetrahydrooctyl-1-dimethylchlorosilane (13F) spaces. Pre- and post-synaptic specializations were identified by immunostaining for synapsin I and microtubule-associated protein-2 (MAP-2). Functional synaptic connections were examined by recording simultaneously from pairs of neurons using the whole-cell configuration of the patch-clamp technique. Spontaneous and evoked synaptic currents were recorded in neurons cultured for 2-14 days. The formation of functional connections was accompanied by the appearance of spontaneous synaptic currents (SSCs), which could be detected after approximately 3 days in culture in the absence of evoked synaptic currents (ESCs). ESCs were detected only after approximately 7 days in culture, mostly in the form of unidirectional synaptic connections. Other forms of synaptic connectivity, such as bidirectional and autaptic connections, were also identified. Both transient GABAergic and glutamatergic signals mediated the transmissions between communicating cells. These results demonstrate the combination of various types of synaptic connections forming simple and complex networks in neurons cultured on line (DETA)-space (13F) patterns. Finally, precisely synchronized SSCs were recorded in neuron pairs cultured on pattern indicating the existence of a fast-acting feedback mechanism mediated by pre-synaptic GABA(A) receptors.
authors.affiliation: Laboratory of Neurophysiology, NINDS, NIH, Bethesda, MD 20892, USA
authors.forename: Q Y
authors.initials: QY
authors.lastname: Liu
authors.forename: M
authors.initials: M
authors.lastname: Coulombe
authors.forename: J
authors.initials: J
authors.lastname: Dumm
authors.forename: K M
authors.initials: KM
authors.lastname: Shaffer
authors.forename: A E
authors.initials: AE
authors.lastname: Schaffner
authors.forename: J L
authors.initials: JL
authors.lastname: Barker
authors.forename: J J
authors.initials: JJ
authors.lastname: Pancrazio
authors.forename: D A
authors.initials: DA
authors.lastname: Stenger
authors.forename: W
authors.initials: W
authors.lastname: Ma
mesh_terms: D000473:Alkanes / Q000494:pharmacology; D000818:Animals; D018929:Cell Culture Techniques / Q000379:methods*; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D002478:Cells, Cultured; D005246:Feedback / Q000187:drug effects / Q000502:physiology; D005260:Female; D005333:Fetus; D058787:GABA-A Receptor Antagonists; D006624:Hippocampus / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D007150:Immunohistochemistry; D007202:Indicators and Reagents / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D009415:Nerve Net / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D009434:Neural Pathways / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D011247:Pregnancy; D051381:Rats; D011963:Receptors, GABA-A / Q000378:metabolism; D012821:Silanes / Q000494:pharmacology; D012826:Silicone Elastomers / Q000494:pharmacology; D013569:Synapses / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D016704:Synapsins / Q000378:metabolism; D013570:Synaptic Membranes / Q000187:drug effects / Q000378:metabolism; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D000473:Alkanes; D058787:GABA-A Receptor Antagonists; D007202:Indicators and Reagents; D011963:Receptors, GABA-A; D012821:Silanes; D012826:Silicone Elastomers; D016704:Synapsins; C410437:tridecafluoro-1,1,2,2-tetrahydrooctyl-1-dimethylchlorosilane; C006194:aminoethyl-aminopropyl-trimethoxysilane; D005680:gamma-Aminobutyric Acid