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Background: We estimated a number of cell populations of peritoneal fluid in rats with experimentally developed peritoneal adhesions., Materials and Methods: The fluid was taken in standarized conditions at the first operation and during reoperation. Animals were divided into four groups. The first group was the control group (n = 20) on which the abdomen was opened and closed without any manipulations (group 1a), and the reoperation was done after 72 hr (group 1b). The other groups (2, 3, 4; n = 20 for each group) were operated, and scarification of the parietal peritoneum and serosa of the bowel was performed. The rats were reoperated after 24, 72, and 168 hr, respectively, after the first surgery. The peritoneal cavity was washed with the 0.9% saline solution. The number of the peritoneal adhesions and populations of the cells were counted., Results: The highest number of peritoneal adhesions was observed in the group of animals reoperated after 72 hr. After 72 and 168 hr, the higher number of mast cells (MC) and neutrophils was observed. The difference was statistically significant. The percentage of mast cells (MC) increased during the experiment. It was different from other cell populations which decreased after 168 hr. The highest change in number was observed for MC. The highest number of MC was observed on the seventh day after the laparotomy., Conclusions: MC influence peritoneal adhesion formation and probably take part in adhesion remodeling. MC and neutrophils changed significantly after manipulations in the peritoneal cavity. Probably, they play an important role in peritoneal adhesion formation.

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.

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.

Production of the oxygen-derived free radicals in peritoneal lavage after one-hour hemorrhagic shock were investigated on a rat model. A statistically significant increased activity of superoxide dismutase (SOD), and an insignificant enhancement of concentration of -SH groups, comparing to the control animals was shown. There was no difference in the level of malondialdehyde (MDA) in the peritoneal fluid from the bled animals and the control group. The results indicate an increased antioxidative potential of the peritoneal content in the early phase of hemorrhagic shock.

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 activity of rat peritoneal cells were assessed by the phorbol mirystinian acetate (PMA)-induced luminol chemiluminescence (LCL). Results in control groups (0 - no manipulation, and I - carotid artery cannulation) were compared with those in the untreated hemorrhagic shock (group II), in the shock treated with the standard polyelectrolyte solution (PES) (group III), and in shock treated with PAF receptor-antagonist BN 52021 + PES (group IV). The maximal and the most rapid LCL was observed in the group treated with BN 52021 (group IV), while chemiluminescent response in the the untreated shock (group II) and in shock treated with PES was minimally expressed and late. The findings indicate for a rapid activation of peritoneal cells during ca 1 hour of hemorrhagic shock. This leads to exhausting their ability to the superoxide anion generation 15 minutes later. Peritoneal cells obtained from the group treated with the BN 52021 revealed a preserved ability to the respiratory burst. It can be concluded that BN 52021 effectively inhibits activation of the PC during hemorrhagic shock.