The development of ACh- and GABA-activated currents in embryonic chick ciliary ganglion neurons in the absence of innervation in vivo

摘要: Chemical synaptic transmission in the chick ciliary ganglion is mediated by nicotinic ACh receptors. Ciliary neurons also express GABAA receptors, although there no known source of GABAergic innervation ganglion, and function GABA receptors on these not known. We examined whether embryonic are regulated presynaptic inputs. Whole-cell currents evoked or soon after dissociation were taken to estimate level functional intact ganglia. destroyed accessory oculomotor nucleus (AON), only input day (E) 4. determined that 80% operations resulted virtual elimination contacts using P65 immunohistochemistry (a vesicle antigen) direct ultrastructural examination. Previous experiments have shown during normal development, ACh-activated increase over sevenfold between E6 E18; GABA-activated twofold, proportion cell size. found ACh- activated uninnervated at E14 E18 as large control responses. Furthermore, receptor-like molecules, visualized with monoclonal antibody 35 immunofluorescence, concentrated high density clusters surface from AON-ablated embryos. affected AON destruction. conclude induced development contact soluble factors released terminals.