Developmental changes in transmitter sensitivity and synaptic transmission in embryonic chicken sympathetic neurons innervated in vitro.

摘要: Dispersed neurons from embryonic chicken sympathetic ganglia were innervated in vitro by explants of spinal cord containing the autonomic preganglionic nucleus or somatic motor nucleus. The maturation postsynaptic acetylcholine (ACh) sensitivity and synaptic activity was evaluated ACh synaptically evoked currents voltage-clamped at several stages innervation. All cells are more sensitive to than uninnervated regardless source cholinergic input. Similarly, medium conditioned either dorsal ventral mimics innervation enhancing neuronal sensitivity. This increase is due changes rate appearance receptors on cell surface. There also nature transmission with development vitro, including an increased frequency events larger amplitude currents. In addition, mean unit current mode increases, as predicted observed Although spontaneous histograms multimodal distributions seen all development, early synapses typically unimodal. Changes between 1 4 days paralleled number that suprathreshold neurons. pre- differentiation described here for interneuronal formed may be responsible efficacy during vivo.