The hare parotid gland: ultrastructure and histochemistry of acinar and ductal cells.

The parotid gland of the hare Lepus europaeus was studied by electron microscopy. The parenchyma consists of secretory areas (acini) and ductal segments (intercalated, striated and excretory ducts). Acinar cells showed a marked heterogeneity due to the presence of secretory granules characterized by different size, electron-density and degree of membrane merging in addition to the occurrence of flattened and dilated rough endoplasmic reticulum. Acinar cells had variable affinity for PAS and PA-TCH-SP staining but were HID- and LIT-TCH-SP negative. Intercalated duct cells lacked secretory granules. Striated ducts were lined by four cell types namely light cells, dark cells, vacuolated cells, and typical striated cells. Excretory ducts showed some scalloping on the apical region of the light cells.