Lacrimal gland fluid secretion and lymphocytic infiltration in the NZB/Wmouse model of Sjögren's syndrome.

Purpose. The fluid secretory impairment of lacrimal and salivaryglands in Sjögren's syndrome (SS) is thought to be related to theextent of lymphocytic infiltration (LI) and subsequent loss of glandular tissue.In this study, we examine the correlation between the extent of tear flowreduction and the extent of LI of lacrimal glands in the NZB/W mouse, a modelof SS. Methods. We stimulated tear production by topical applicationof carbachol onto the gland while fluid was collected from the lacrimal duct.The lacrimal glands were removed after fluid collection for histology. Results. Fluid secretion in response to carbachol was less inthe majority of young NZB/W females compared to C57 control animals and noneof the glands showed LI. Fluid secretion was also impaired in the majorityof old NZB/W females, and the extent of LI was highly variable. Some of theold SW females also showed blunted fluid secretory responses and some degreeof focal LI. Young SW females showed no LI and most animals exhibited normalflow responses. Analysis of paired flow and LI measurements showed no correlationbetween LI and flow impairment in any of the groups or in the pooled data.Carbachol-stimulated protein secretion from lacrimal gland slices in vitro were similar in young and old SW and NZB/W mice. Conclusions. These results suggest that LI alone is not sufficientto explain the secretory dysfunction in the NZB/W mouse model of Sjögren'ssyndrome. [ABSTRACT FROM AUTHOR]