Age-related histomorphometric changes in labial salivary glands with special reference to the Acinar component

Purpose: To evaluate histomorphometric age-related changes in labial saliva ry glands (LSG) of healthy subjects, with special reference to the mucous a nd seromucous acini. Method: Investigation of age-related histomorphometric changes was conducte d on 120 samples of LSG obtained from autopsy subjects free of salivary gla nd tumors/diseases. Samples were divided into young (<0 years, n = 30), adu lt (30-60 years, n = 45) and old (> 60 years, n = 45) age groups. Measureme nts were performed an hematoxylin and eosin stained slides. Parenchymal com ponents included acini and ducts. The acinar component was presently analyz ed separately in respect to mucous acinar cells and seromucous acinar cells . Mucous acinar cells presented pale eosinophilic cytoplasm, while that of the seromucous was darker and basophilic. Stromal components included conne ctive tissue, blood and lymphatic vessels, inflammatory infiltrate and adip ose tissue. The mean volume fraction (V-v) of all components in each age gr oup was calculated. Statistical analysis was performed by one-way ANOVA and Tamhane tests. Results: The mean V-v of the seromucous acinar cells decreased by 49.3% (p < 0.0001) and that of the mucous acinar cells decreased only by 28.5% (p = 0.0001). Changes in the ducts were statistically non-significant (p = 0.312 ). Of the stromal components: the mean V-v of the adipose tissue showed the highest increase, 2768% (p < 0.0001) followed by the inflammatory infiltra te, 512% (p < 0.0001). Conclusions: The marked decrease in the V-v of seromucous acinar cells acco mpanied by a lower decrease in the V-v of mucous acinar cells may explain a ge-related changes in LSG secretion. These findings could bear important im plications regarding functional age-related changes of these glands. (C) 20 00 Elsevier Science Inc. All rights reserved.