Adrenergic and cholinergic nerve terminals in the rat parotid gland. Electron microscopic observations on permanganate-fixed glands



The innervation of the acinar cells of the rat parotid gland was studied using potassium permanganate fixation. Adrenergic terminals, characterized by the presence of small granular vesicles, and cholinergic terminals, containing small agranular vesicles, made close contact with the acinar cells. Both adrenergic and cholinergic terminals were observed in contact with the same cell, and subsurface cisterns of endoplasmic reticulum were found in relation to the contact areas of both types of endings. In addition, both adrenergic and cholinergic axons were found within the same Schwann cell sheath in the connective tissue spaces.