Search

Mast cells (MC) produce, store and release many biologically active substances, especially inflammatory factors, chemotactic substances for neutrophiles, cytokines and prostaglandins. They play very important role in fibrinosis and they are an important factor in peritoneal adhesions formation and lysis. In this study we tried to evaluate role of mast cells in peritoneal adhesions formation. We estimated number of mast cells in peritoneal fluid in rats with experimentally developed peritoneal adhesions. The number of mast cells per ml was counted in flow cytometry in specimens of peritoneal fluid taken from operated rats. The fluid was taken in standardized conditions the same for each group at the first operation and during reoperation. Peritoneal cavity was washed with 0.9% Saline solution. MC were visualized using indirect immunohistochemical method LSAB with mouse antibody. The animals were divided into 4 groups. 1 st group was control group (n=20) on which the abdomen was opened and closed without any manipulations, and the reoperation was done after 72 hours. The other groups (2, 3, 4; n=20 for each group) were operated and scarification of the partial peritoneum and serosa was performed. The rats were brought back to conscious and then were reoperated respectively after 24, 72 and 168 hours after first surgery. After the laparotomy and damage of the peritoneum we observed formation of the peritoneal adhesions between intestine loops and between intestines and damaged parietal peritoneum. Also the higher number of mast cells was observed in the groups of animals with damaged peritoneum. The highest number of peritoneal adhesions was observed in the group of animals reoperated after 72 hours. After 72 and 168 hours the higher number of MC and neutrophils was observed. The difference was statistically significant. The percentage of mast cells was increasing during the experiment duration. It was different from other cells populations which decreased after 168 hours. The MC and neutrophils were cell population which changed significantly after manipulations in peritoneal cavity. It is very probable that they play an important role in peritoneal adhesions formation.

Mast cells (MC) are source of many biological active compounds like cytokines, arachidonic acid derivates, proteoglicanes, prostaglandins, proteases, free oxygen radials, NGF, PAF and many more. The role of MC in pathogenesis of Hirschsprung's disease (HD) is not clear. Substances produced by MC may exert an important effect on embryology, growth, differentiation and regeneration of intestinal nervous system. Additionally, MC products modulate inflammation processes thus influencing on the clinical course of HD. Present study was established to evaluate the morphologic MC examination as a support of making diagnosis in HD. The MC topography and morphometry were evaluated in specimens collected from aganglionic colon of patients with diagnosed HD. The results were compared with corresponding data from normally innervated colon of patients suffering from constipation, and normal colon of children not presenting defecation problems. MC were visualized using indirect immunohistochemical method LSAB with mouse antibody against human tryptase. The MC visualized in submucosa and muscular layer in Hirschsprung's disease were significantly larger in comparison with control group (p<0.05). Also the number of MC/mm2 in mucosa and lamina propria in HD was significantly elevated (p<0.05). However, the MC density in submucosa was also higher but it was not high statistically significant. In muscular layer and in serosa density of MC/mm2 was not statistically significant. In the intestinal wall MC in aganglionic segment in Hirschsprung's disease are significantly activated comparing with normally innervated colon segments taken from the patients from other groups. This may confirm the role of MC both in pathogenesis of HD and in the reparation processes of bowel nervous system.

In the course of a hemorrhagic shock, pathological changes occur, which result in intensifying the insufficiency of various vital organs. It can also lead to the development of the multiorgan dysfunction syndrome (MODS) that is the cause of high posthemorrhagic mortality. As a result of the ischemia in the lung there appear proinflammatory factors that mobilize and activate mast cells, inducing degranulation in them. The aim of the study was the analysis of cellular composition and cytomorphometric evaluation of mast cells present in the lavage fluid from the pleural cavity of rats in a sham operated group and in the group presenting hemorrhagic shock. The results revealed an increase of the total cell count in the lavage fluid from the pleural cavity. In the cytological smears a statistically significant accumulation of inflammatory cells was present, especially neutrophils. The increase in mast cells and eosinophils number was not statistically significant. There was not a change in the morphometric parameters of mast cells except the circularity index. A decline of the circularity index indirectly may suggest the degranulation of mast cells, which reflects an inflammatory process in the lungs.

The activation of mast cells (MC) and liberation of their mediators can play an essential role in initiating and controlling inflammatory processes in the wall of the gastrointestinal tract (GIT) due to ischemia. The role of MC in changes induced by hemorrhagic shock (HS) remains unknown. Heparin provided by MC seems to inhibit local inflammation and prevent DIC. The aim of this study was to evaluate the morphometric changes and biochemical activity of MC in the stomach wall after 75 minutes of hemorrhagic shock. The MC in mucosal, submucosal, muscular and serosal compartments of the various stomach wall regions were examined in shocked rats and in the control group. Additionally, the contents of glycosaminoglycans (GAG), measured as uronic acids concentration, as well as anticoagulative activity in the stomach wall were assessed. HS resulted in an evident increase in the number of mast cells detected in the stomach mucosa and serosa, in slight alterations in number of MC in the submucosal and muscular layers, a significant increase in size and changes of the shape of the MC. The elevation of the width, area, and circular shape of MC in all layers were noted. No clear and significant differences between various stomach regions in MC numbers and MC sizes could be shown. No reaction of other inflammatory cells at this stage of shock was observed. Highly significant increases in GAG concentration, and anticoagulative activity in the stomach wall due to shock were noted. The morphometric and biochemical data may indicate MC activation, especially in mucosa and serosa. The shock-induced migration of MC settled in the stomach wall seems to be possible. The results suggest an essential role of MC reaction in the stomach wall in the early phase of hemorrhagic shock.

An extensive blood loss activates generalized inflammatory response. Abdominal organs and especially intestines are very sensitive to the ischemia-reperfusion insults due to hemorrhagic shock (HS) and blood volume restoration. Previously obtained results suggest that studies on peritoneal lavage fluid (PLF) can contribute to elucidation of inflammatory processes in abdominal organs in HS. Histamine (H) levels, total cell, and mast cell (MC) numbers, and MC ultrastructure in the fluid lavaged from peritoneal cavity were compared in the following groups of rats: control (gr. 1), sham operation (gr. 2), untreated hemorrhagic shock (gr. 3), shock treated with blood volume restoration with lactated Ringer's solution (LR) (gr. 4), shock treated with platelet activating factor (PAF)-receptor antagonist Ginkgolide B (BN52021), and LR (gr. 5). A shock-related significant increase in total cell numbers, MC numbers, MC degranulation, and histamine levels in PLF were observed. The restoration of blood volume caused further elevation of the above phenomena (gr. 4) while BN52021 seemed to inhibit peritoneal MC mobilization and degranulation as well as to attenuate increase in peritoneal H level (gr. 5). The peritoneal cavity is a place of rapid and strong reaction to hemorrhage. Evaluation of peritoneal histamine levels might be helpful in the monitoring of shock dependent intra-abdominal processes. Peritoneal MC mobilization and degranulation, and increase in histamine level is inhibited by BN52021.

The mast cells and eosinophils washed out from rat peritoneal cavity after 75 minutes of untreated hemorrhagic shock were studied in light and electron microscope. A significantly increased total peritoneal cell (PC) number, an increased mast cell (MC) number, decreased eosinophil number, and features of activation of both MC and E were found: heterogeneity and combining of granules, evacuation of their content, build up and enlargement of endoplasmic reticulum, development of microtubular cytoplasmic system, multiplication of cell membrane microvilli, and contacts between MC and E. Ultrastructural examination revealed vesicle formation in Golgie apparatus. These vesicles created characteristic blebs on the cell surface and evacuated their contents outside. Morphological findings suggest that peritoneal mast cells and eosinophils are involved in mechanism of the intestinal injury in shock.

The morphology and functions of gastrointestinal mast cells (MCs) under physiological and pathological conditions were described. Special attention was paid to the MCs origin, differentiation and morphological and biochemical aspects of their degranulation. Mast cells are important component of normal architecture of the gastrointestinal tract. Many substances released from MCs during degranulation are biologically active and mediate numerous processes: blood flow regulation, epithelial and endothelial permeability, mucosal secretion, gastrointestinal tract motility, immunological events related to the antigens of various origin, angiogenesis, cancer development. Thus MC is often considered as an important agent in pathogenesis of many gastrointestinal diseases. The gastrointestinal diseases which was described in this paper are following: bacterial and parasitic infections, peptic ulcer, ulcerative colitis, Leśniowski-Crohn's disease, inflammatory polyps, intestinal graft-versus-host reaction, neoplastic tumors, mastocytosis, intestinal ischemia.