Epithelial-stromal interactions in salivary glands of rats exposed to chronic passive smoking.

ABSTRACT

OBJECTIVES: Cigarette smoke leads to precancerous and cancerous lesions in the mouth even when the exposure is passive. The salivary glands are amongst the tissues exposed to the smoke but it is unclear whether or not passive cigarette exposure is related to detectable changes in these tissues. The objective of this study was to observe the tissue architecture of the parotid and submandibular glands in rats after passive cigarette exposure and to measure any changes that occurred. DESIGN: Twenty Wistar rats were divided into 10 non-smoking animals and 10 animals exposed to cigarette smoke. After 6 months of smoke exposure samples were collected from both exposed and unexposed salivary glands for histological examination under both transmitted and polarized light microscopy. RESULTS: Changes in the glands of exposed animals included involution of the cytoplasm and nucleus of the acinar cells and the presence of an inflammatory infiltrate. There was an abnormal accumulation of type I collagen in the stroma and an enlarged interacinar space filled with extracellular matrix. CONCLUSION: Passive smoking led to substantial structural changes in the salivary glands which could significantly affect function.