Cellular specialization of synaptic integration in a mammalian sympathetic ganglion

[摘要] Sympathetic ganglia are widely viewed as simply relays that are essential to convey neural activity from spinal preganglionic neurons to distinct peripheral targets. However, recent studies indicate that synaptic integration in sympathetic ganglia is more complex than that of a simple excitatory relay. It is proposed that synaptic organization of each functional subset of sympathetic ganglion cells is specialized to generate a unique synaptic gain function, thereby allowing for differential control of specific target modalities. This dissertation describes cellular specialization of some critical determinants of synaptic gain in rat superior cervical ganglion (SCG) neurons. The work was first focused on identifying presynaptic stimulus threshold and NPY immunoreactivity as neuronal classification criteria of secretomotor, pilomotor and vasoconstrictor cells. The results here show that these three functional phenotypes of neurons are indistinguishable in terms of synaptic convergence. Furthermore, norepinephrine (NE) causes different modulatory effects upon pre and postsynaptic ¦Á2-adrenergic receptors in these cell types. Collectively, this work characterizes cellular specialization of synaptic convergence and NE neuromodulatory mechanism that are involved in synaptic integration in the rat SCG.

[发布机构] the University of Pittsburgh

[效力级别] blood pressure