Human thyroid C cells: occurrence and amine formation studied by perfusion of surgically removed goitrous glands.

Abstract

ABSTRACT Surgically removed lobes from nonmalignant human goiters were oxygenized and perfused ex vivo, and pieces were taken for silver staining, fluorescence histochemistry of certain arylethylamines, and fluorometric determinations of dopamine. Groups of parafollicular argyrophilic cells, probably identical with the calcitonin-producing C cells, were detected in the thyroid lobes. The cells contained no fluorogenic amine and no dopamine could be measured. After perfusion with l-3,4-dihydroxyphenylalanine (l-dopa), all argyrophilic cells showed a bright green formaldehydeinduced fluorescence and chemical determinations revealed the formation of dopamine in the gland. Since no other fluorescent structures appeared after the perfusion it can be assumed that the newly formed dopamine was present in the population of argyrophilic cells. The dopamine-containing C cells could be demonstrated in smears from fine-needle aspiration biopsies of the perfused lobes. The argyrophilic (fluorescent) cells were more nu...