Modulatory actions of norepinephrine in the central nervous system.

摘要: Early studies have shown that norepinephrine (NE) released synaptically or iontophoretically onto neurons in the central nervous system acts to depress firing by a mechanism associated with hyperpolarization but no change an increase membrane resistance. This contrast classical transmitters, which cause conductance increase. Recent designed clarify functional implications of these biophysical actions revealed new phenomenons major overall effect NE on cerebellar Purkinje cells is enhance conventional synaptic input and induce signal-to-noise ratio evoked versus spontaneous activity. via stimulation locus coeruleus also has been found inhibitory effects gamma-aminobutyric acid, endogenous transmitter. The appear even at low doses having direct depressant action Specificity tests enhancement glycine-induced inhibition inability dopamine mimic NE. hypothesis presented significant bias alters postsynaptic responsiveness transmitter systems, themselves may be more directly concerned detailed information transfer.