Infiltration of Lymphocytes and Mast Cells to Bladder Tissues in Experimental Models of Interstitial Cystitis/Bladder Pain Syndrome

 A different degree of severity of inflammation was detected in the bladder biopsy specimens; however, the cellular mechanisms of inflammation in interstitial cystitis/bladder pain syndrome (IC/BPS) and the processes leading to tissue damage and fibrosis are not yet completely clear.

 The aim of this study was to determine the leukocyte and mast cell infiltration to the bladder tissue in various experimental models of IC/BPS.

 Various IC/BPS models have been generated using white New Zealand rabbits. Animals were divided into 4 groups depending on the type of the model: (1) The introduction of 0.5% HCl into the bladder; (2) The introduction of urine taken from the bladder into the wall of the bladder; (3) The introduction of 0.9% NaCl; (4) Intact animals. The number of cells in the tissues of the bladder was evaluated in points and histological analysis of the tissues of the bladder wall was performed. The analysis was carried out after 14 days of modeling.

 Mast cells were determined only in groups 1 and 2 (P < 0.001). In the 2nd group, developing necrosis and mixed inflammatory infiltration, giant, necrotic, multinucleated histiocytes were noted. In group 3, tissue edema and single scattered lymphocytes were noted.

 The association of high inflammatory cell infiltration in the chemical version of the IC/BPS model and mast cell infiltration with impaired bladder integrity has been established.