The leukocytic response in ligated rat submandibular glands

Within 1 h after ligation of the main excretory duct of the rat submandibular salivary gland neutrophils begin to migrate into the parenchymal epithelium and by 18 h they accumulate, unchanged, within the lumina of acini and intralobular ducts. By 24 h, monocytes become the predominant intraepithelial migrating cell type. These selectively migrate into lumina of convoluted ducts where they phagocytize intraluminal material consisting of secretion products, egested cell debris and neutrophils. By 4 days monocytes laden with phagosomes begin to migrate into the stroma and by 17 days relatively few leukocytes remain within the parenchyma. Changes in ligated gland weight reflect the cytological changes. It is concluded that in experimental obstructive adenitis monocytes play a most important role while neutrophils are adventitious.