Mast cells in accessory glands of experimentally induced prostatitis in male Wistar rats

We studied the histological modifications in the accessory glands of autoimmune rats. Adult male Wistar rats were id immunized three times with saline extract of rat male accessory glands (RAG) chemically modified (MRAG) in complete Freund's adjuvant (CFA) (groups 1, 2, and 3). Prior to the first immunization with MRAG-CFA groups 2 and 3 received peritoneal cells obtained from rats that had been injected 2 or 24 hr previously with low doses of RAG. Furthermore, an additional group (group 4) ip immunized with liposome-associated-RAG was incorporated. The delayed-type hypersensitivity response studied 10 or 15 days after first immunization was positive for rats of groups 1, 3, and 4, while it was negative for rats of group 2. Serum samples obtained on Day 45 and studied by ELISA showed high levels of autoantibodies in groups 1 and 2 and lower levels of autoantibodies in group 3, but did not show autoantibodies in group 4. The histological studies performed 10 days after the last immunization showed organ-specific lesions in the accessory glands in animals of groups 1, 3, and 4. Infiltration of mononuclear cells was the main alteration in group 1, while infiltration of mast cells and polymorphonuclear leukocytes were present in specimens of groups 3 and 4. The main finding of this study was a significant increase (P < 0.0005) in the extent of mast cell degranulation in the specimens of accessory glands stained with toluidine blue. Our results suggest that mast cells are activated in our experimental model of autoimmune disease.