Spinal motor neuron shares the same neurotransmitter (ACh) with sympathetic preganglionic neuron.Can spinal motoneurons establish synapses with sympathetic postganglionic neurons? In this study,superior cervical ganglion neuron (SCGN) were labeled by DiI,and SMN-SCGN synaptic model were established by co-culture.Co-culture was double-immunofluorescently labeled by synatophysin (p38) antibody and ChAT antibody to illustrate the synaptogenesis in the presynaptic neurons,followed by quantitative study.Western blot and RT-PCR were also performed to confirm the changes of p38 content in the co-culture.Miniature spontaneous postsynaptic current (mSPC) was recorded in SCGN so as to observe the influence of co-culture and verify the formation of functional synapses.We found:(1) Primary culture of SMN and SCGN achieved satisfactory growth states.