Immunofluorescence of dopamine-beta-hydroxylase in small intensely fluorescent cells of human sympathetic ganglia.

Thoracic and lumbar sympathetic ganglia of human males were investigated using a method for the consecutive demonstration of catecholamines and catecholamine synthesizing enzymes in fluorescence microscopy. In the thoracic ganglion, a minor population of small intensely fluorescent (SIF) cells, identified by glyoxylic-acid-induced fluorescence, exhibited positive indirect immunofluorescence after incubation with antibody to dopamine-beta-hydroxylase (DBH). SIF cells in the lumbar ganglion exclusively stained DBH-negative. The findings indicate the presence of two SIF cell populations in the thoracic ganglia of the human sympathetic trunk, one containing dopamine and the other containing norepinephrine and/or epinephrine. In lumbar ganglia, only dopamine-storing SIF cells appear to be present.