The adrenergic innervation of the gall-bladder of healthy persons and patients suffering from cholecystitis has been studied following fluorescence histochemical methods.The normal gall-bladder is moderately innervated by adrenergic nerve fibres. Fine nerve fibres have been observed in the lamina propria, fibromuscularis and serosa. Catecholamine-containing fluorescent cells have been observed at different sites and their possible role as chemoreceptors and their endocrine nature have been reaffirmed. Adrenergic nerve fibres show signs of degeneration in cholecystitis as is evidenced by swelling of the nerve fibres and enhanced intensity of fluorescence in fluorescent cells.