Involvement Of Dopaminergic Sif Cells Of Rat Superior Cervical-Ganglion In Response To Chemoreceptor Stimuli

Until the past decade sympathetic ganglia were considered to be a two-neuron system consisting of cholinergic preganglionic nerve terminals, noradrenergic dendrites, and cell bodies of postganglionic neurons. This simple picture was complicated by the discovery of small cells of chromaffin type (1)—the small intensely fluorescent (SIF) cells. The postganglionic neurons control the function of sympathetic tissues by innervating numerous target organs. The carotid bodies, pineal gland, brain blood vessels, salivary glands, iris, and heart receive fibers originating from the superior cervical ganglion (SCG), but the function of SIF cells still is elucidated poorly.