SPRAY OF PHOSPHOLIPID POWDER REDUCES PERITONEAL ADHESIONS IN RABBITS

Background : The possible effects of peritoneal dialysis and a combination of two exogenous phospholipids, dipalmitoylphosphatidylcholine (DPPC) and phosphatidylglycerol (PG), on experimentally induced intraperitoneal adhesion formation in rabbits were compared. Methods : Fifty New Zealand rabbits equally divided in five groups underwent a midline laparotomy to create a right iliac fossa 5 × 1 cm parietal peritoneal defect and a matching defect over the adjacent large bowel. In 10 control rabbits (group I) the abdominal wound was closed without any further intervention. Twenty rabbits forming groups II and III underwent two sessions of peritoneal dialysis, one following abdominal closure and the second 24 h later, through a catheter placed at surgery. Rabbits in group III received an intraperitoneal injection of DPPC and PG after each session of dialysis. In 10 animals (group IV) a DPPC gel was applied to the defect over the large bowel and in 10 animals (group V) the peritoneal cavity was sprayed with a ‘puff’ of DPPC:PG (7:3) powder prior to abdominal closure. All the animals were killed a week after the laparotomy to assess the extent of adhesion formation. Results : The formation of adhesions was reduced in all the groups compared to the controls but a statistically significant difference was observed only in the group receiving the intraperitoneal ‘puff’ of DPPC:PG powder. Conclusion : A combination of DPPC and PG sprayed as a ‘puff’ intraperitoneally reduces experimentally induced peritoneal adhesions in rabbits.     

奥曲肽联合透明质酸钠预防兔术后腹膜粘连的疗效评价

目的: 观察奥曲肽联合透明质酸钠预防兔术后腹膜粘连的效果。方法:建立兔术后腹膜粘连模型,然后分为4组：（1）术中不用药物处理设为模型对照组;（2）关腹前局部涂抹透明质酸钠设为透明质酸钠组;（3）关腹前腹腔内注射奥曲肽设为奥曲肽组;（4）关腹前局部涂抹透明质酸钠同时腹腔内注射奥曲肽设为联合组。术后14d剖腹观察,判定腹膜粘连程度等级。结果:4组粘连发生率比较无统计学意义(χ2＝3.51, P>0.05);联合组重度粘连发生率(8.3%)显著低于其它3组（分别为66.7%,33.3%,25.0%）(均P<0.01)。奥曲肽组和透明质酸钠组两组的粘连级别近似（P> 0.05）。结论:奥曲肽和透明质酸钠均可减轻实验性腹膜粘连的程度和重度腹膜粘连发生率,两者合用其作用更明显,表明两药合用具有降低粘连的协同作用。     

Does hyaluronic acid-carboxymethylcellulose (HA-CMC) membrane interfere with the healing of intestinal suture lines and abdominal incisions?

Although hyaluronic acid-carboxymethylcellulose (HA-CMC) membrane has the advantage of preventing intraabdominal adhesions, it has theoretical risk of negative effects on the healing of intestinal suture lines by forming a barrier between the suture lines and neighboring serosal surfaces. This study evaluated the effect of HA-CMC on bowel anastomoses, scar healing, and intraabdominal adhesion formation. Two groups of 10 male Sprague-Dawley rats were examined. In the first group, laparotomy was performed with a median incision. Colotomy on the cecum and a single-layer repair of the bowel wall was performed. HA-CMC membrane was placed on the cecal suture line and under the laparotomy incision before abdominal closure. The second group had the same procedure but no HA-CMC membrane was placed. The animals were killed on postoperative day 14. Intraabdominal adhesions, laparotomy suture line endurance, bursting pressure of the repaired cecal wall, and tissue hydroxyproline levels were determined. The repaired cecal wall was also examined histopathologically. The statistical analyses revealed that HA-CMC prevented intraabdominal adhesions significantly. No negative effects of this material on the healing of the bowel and laparotomy suture lines were observed. HA-CMC appears to be a safe material to prevent intraabdominal adhesions, without negative effects on the healing of abdominal incisions and bowel suture lines.     

Influence of phosphatidylcholine on intra-abdominal adhesion formation and peritoneal macrophages

Phosphatidylcholine (PC) is the predominant constituent of the surface-active material coating peritoneal mesothelium. Its effects on surgically induced adhesion formation and on peritoneal macrophage viability and superoxide production were studied in rats. Rats treated with intraperitoneal PC liposomes showed more adhesions than controls (p less than 0.01). In vitro incubation with PC had no effect on macrophage viability, but significantly diminished superoxide production (p less than 0.05 and less). It is concluded that PC in its insoluble form is of no value in the prophylaxis of adhesions after abdominal and pelvic surgery and that with the use of the intraperitoneal route it is probably contraindicated in patients undergoing continuous ambulatory peritoneal dialysis.     

Prevention of intraperitoneal adhesions by intraperitoneal lavage and intraperitoneal 5-fluorouracil: experimental studies

Postoperative adhesions remain the leading cause of small bowel obstruction. Peritoneal adhesions were induced in 180 rats by scraping the cecum and burning the adjacent parietal peritoneum by electrocoagulation. The adhesions were scored 14 days later in a blinded manner. All four types of intraperitoneal instillations significantly reduced the extension and the severity of the adhesions, at both schedules, when compared to the control group. The use of 5-fluorouracil at 20 mg/kg in peritoneal dialysis solution during 5 days significantly decreased the global score (P = 0.04), the extension (P = 0.04), and the severity (P = 0.04) of adhesions when compared to the 5-day instillation of peritoneal dialysis alone. Lavage of the abdomen with peritoneal dialysis solution or hetastarch decreased the formation of adhesions. Instillation of 5-fluorouracil in a large volume of peritoneal dialysis solution could be novel and promising treatments for prevention of postoperative adhesions.     

In vivo expression of thrombospondin-1 suppresses the formation of peritoneal adhesion in rats

BACKGROUND Formation of intraperitoneal adhesions is one of the major complications after abdominal surgery, which may lead to bowel obstruction. Thrombospondin 1(TSP-1) is an extracellular matrix modulating glycoprotein during tissue regeneration and collagen deposition.AIM To evaluated the therapeutic potential of overexpressed TSP-1 in suppressing pelvic adhesion formations in rat models.METHODS Pelvic adhesion was induced in anesthetized rats by laparotomy cecal abrasion.The animals were randomly assigned to treatment of local application with Seprafilm(an antiadhesive bioresorbable membrane) or adenoviral vectors encoding mouse TSP-1(AdTSP-1) on the surfaces of the injured cecum. The severity of the peritoneal adhesions was evaluated by blinded observers 14 d later.RESULTS Compared with control(no treatment) group, the application of Sperafilm significantly reduced the formation of adhesion band, and local administration of AdTSP-1 on the injured cecum the also attenuated the severity of peritoneal adhesion score. However, systemic delivery of AdTSP-1 did not affect the formation of adhesion.CONCLUSION We conclude that therapeutic approaches in inducing regional overexpression of TSP-1 may serve as alternative treatment strategies for preventing postoperative peritoneal adhesion.     

Preventing recurrent postoperative adhesions: an experimental study in rats

A peritoneal lavage model, cyclic intraperitoneal lavage (CIPL), and other adhesion preventing methods with and without fibrinolytic agents were compared to a control group without treatment in an animal study. The adhesion-preventing effect was evaluated at the site of a standardized peritoneal defect (free peritoneal grafting, P) and at the laparotomy wound (L) of 60 rats (12 escape) after surgical lysis of primary adhesions during relaparotomy In five test groups with different treatments and in a control group without treatment recurrent adhesions were investigated during relaparotomy according to an adhesion grading scale with increasing severity (O-III). In the control group only severe adhesions grade II and III were observed. The five test groups showed different distributions of grade 0-II adhesions: compared to the control group a significant difference of the preventing effect was seen after CIPL with 1.36% glucose solution (as used for peritoneal dialysis) and after CIPL with Ringer's solution at the sites P and L, after a one-time irrigation with Ringer's solution only at the peritoneal graft P. Fibrinolytic agents used in CIPL or as single dose application failed to show an improvement compared to the control group.     

Reduction in postoperative adhesion formation and re-formation after an abdominal operation with the use of N, O - carboxymethyl chitosan

BACKGROUND: Postoperative adhesions have proven to be intractable complications after abdominal operations. This study assessed the efficacy of N, O - carboxymethyl chitosan (NOCC) to limit adhesion formation and re-formation in a rabbit abdominal surgery model. METHODS: In study 1 (adhesion formation), injuries to the large bowel, cecum, and abdominal sidewall were generated in rabbits. The rabbits (10/group) were randomly assigned to 1 of 5 treatment groups: Group A received no NOCC treatment; in group B, NOCC gel was applied directly to the injured site and NOCC solution was applied throughout the abdominal cavity; in group C, NOCC gel was applied near the injured site and NOCC solution was applied as above; in group D, NOCC gel was applied distant to the injury and NOCC solution was applied as above; in group E, a mixture of NOCC gel and solution was applied at the injured site. Adhesions were evaluated 14 days later. In study 2 (adhesion re-formation), adhesions were generated as above but were then lysed by careful dissection. After adhesiolysis, the rabbits (9/group) were treated with NOCC gel and solution at the site of adhesiolysis or left untreated. Adhesion re-formation was assessed 14 days later. In study 3 (mechanism of action), sterile tissue culture plates were coated with NOCC and adhesion of cultured, radiolabeled murine fibroblasts to the plates was assessed. RESULTS: In study 1, animals treated with NOCC gel and solution showed reduced adhesion formation (P<.01). NOCC gel was equally efficacious if applied on the site of injury or near the site of injury but less efficacious if applied at a site distant to the injury. In study 2, animals treated with NOCC gel and solution showed less adhesion re-formation compared with the untreated control animals (P<.01). In study 3, murine fibroblasts did not adhere to NOCC-coated tissue culture plates. CONCLUSIONS: NOCC gel and solution can reduce adhesion formation and re-formation in this rabbit model. The inability of fibroblasts to adhere to NOCC solution-coated surfaces suggests that NOCC may act as a biophysical barrier.     

Surgical adhesions: evidence for adsorption of surfactant to peritoneal mesothelium

BACKGROUND: It has been speculated that the formation of surgical adhesions must be preceded by physical adhesion of the two surfaces, a process normally prevented by a lining of adsorbed surface-active phospholipid (surfactant) acting as both a superb boundary (solid-to-solid) lubricant and a release (antistick) agent. Animal trials administering exogenous surfactant as a dry powder (ALEC) have previously demonstrated a reduction of 80% in abdominal adhesions. METHODS: Incubation of rat peritoneum (both live and excised) with radiolabelled dipalmitoyl phosphatidylcholine (DPPC) has been used to demonstrate adsorption; while the normal lining of surfactant in the human abdominal cavity has been confirmed by epifluorescence microscopy using Phosphin E as the hydrophobic probe. AIMS: The overall aim is to confirm that peritoneal mesothelium has a lining of surfactant known for its lubricating and release properties, and that this lining can be enhanced by the adsorption of exogenous material. RESULTS: Adsorption of DPPC to peritoneal mesothelium was 470 ng/cm2 (n = 8) ex vivo and 598 ng/cm2 (n = 18) in vivo, these rates being enhanced by EggPG by 62% ex vivo and 47% in vivo to reach the equivalent of almost three close-packed monolayers. CONCLUSIONS: These results can explain the reduction in surgical adhesions previously reported in animals by administering ALEC (7:3 DPPC:EggPG) as a highly surface-active dry powder, although it is now used in saline suspension to treat respiratory distress syndrome in newborns, in whom it has no side-effects. These findings would appear to justify clinical trials for dry ALEC in suppressing surgical adhesions with minimal risk of an adverse reaction. The results of these trials are also discussed and found to be compatible with the known ability of surfactant to resist physical adhesion by fibronectin, the tacky 'glue' by which fibroblasts attach to surfaces as the first step in formation of fibrinous adhesions.     

Efficacy of a hyaluronan derivative gel in postsurgical adhesion prevention in the presence of inadequate hemostasis.

BACKGROUND: We previously demonstrated that an auto-cross-linked hyaluronan-based antiadhesion agent (auto-cross-linked polysaccharide [ACP] gel) was effective in postsurgical adhesion prevention after open laparotomy and laparoscopic surgery with adequate hemostasis in animal models. This study assessed the ability of different preparations of ACP gel to prevent adhesions in the presence of bleeding or inadequate hemostasis. METHODS: Ninety-seven female rabbits were subjected to a standardized surgical lesion with subsequent exudative abdominal bleeding (oozing model), and 97 animals were subjected to a standardized surgical lesion with severe abdominal bleeding (bleeding model). After injury, the animals were randomly assigned to 5 groups of treatment: 3 different preparations of ACP gel (20, 40, and 60 mg/mL), a hyaluronan-carboxymethylcellulose film, and no treatment. Three weeks after operation, the animals were killed, and the adhesions were assessed by a blinded observer who measured the length and area of the adhesions and who used the Blauer scoring system. RESULTS: All 3 preparations of ACP gel and the hyaluronan-carboxymethylcellulose film reduced adhesion formation in both models (P <.01) as measured by the number of adhesion-free animals, mean Blauer score, and the mean length and surface area of the adhesions. There were no statistical differences between the different treatment groups. CONCLUSIONS: These data suggest that different hyaluronan based agents in the presence of severe bleeding or exudative abdominal bleeding reduce de-novo postsurgical adhesion formation.     

Preliminary assessment of postoperative adhesion formation after laser-assisted mesh fixation to the peritoneal surface

OBJECTIVE: This study evaluated the incidence and persistence of adhesions following intraperitoneal onlay mesh fixation with tissue soldering in an experimental model. METHODS: Anesthetized New Zealand white rabbits (n = 21), weighing 2.8-3.2 kg, underwent laparotomy. Controls (group 1 [n = 3]) had 2 x 2 cm Mersilene (Ethicon, Somerville, New Jersey) polyester mesh segments fixed to the peritoneum with staples (USSC, Norwalk, Connecticut). Group 2 (n = 7) rabbits had Mersilene mesh affixed by melting 55% collagen solder using a prototype laser (1.43 micro, 2.5 W CW, 4 mm spot size, 60 degrees C set temperature) over mesh. Group 3 (n = 6) rabbits had Vicryl (Ethicon, Somerville, New Jersey) polyglactin mesh embedded in 60% collagen solder placed onto the peritoneum and fixed with identical laser parameters as group 2. Group 4 (n = 5) rabbits had 55% collagen solder placed and Mersilene pressed into it after melting. Four segments were placed in each experimental animal. Animals were euthanized at 2, 4, or 6 weeks. Adhesions were graded (0 = none; I = filmy adhesions; II = omental; III = bowel adhesions gently lysed; IV = dense adhesions requiring sharp dissection). RESULTS: Grade III adhesions were observed in both control and group 4 animals at 2 weeks, persisting in group 4 animals at 6 weeks, but having lysed in controls at 6 weeks. No adhesions were present in group 3 specimens at any interval. Grade I adhesions were present in group 2 at 2 weeks at exposed mesh areas, and declined in frequency at 6 weeks. Evidence of reabsorption of the polyglactin mesh-solder composite was apparent in the group 3 specimens at 4 weeks, and complete resorption had occurred by 6 weeks postoperatively. DISCUSSION: Laser-assisted solder fixation caused minimal adhesion formation when mesh was covered by solder. Adhesions were observed if Mersilene mesh material was exposed to the abdominal contents. Vicryl mesh-solder composites reabsorbed without inflammation, scarring, or adhesions at the sites of mesh fixation. CONCLUSION: Further development of this technology is warranted.     

Effects of surgical gloves on postoperative peritoneal adhesions and cytokine expression in a rat model

BACKGROUND: Postoperative intraperitoneal adhesions are a major cause of morbidity. We studied the effects of synthetic and latex gloves, and their powders, on postoperative adhesions and cytokine expression in a rat model. METHODS: Rats underwent laparotomy and cecal abrasion. Rats were grouped based on the glove type used: synthetic powder-free (SPF), synthetic powdered (SP), latex powder-free (LPF), and latex powdered (LP). Serum cytokine (tumor necrosis factor [TNF], interleukin-1 [IL-1], and IL-6) levels were measured. Animals were killed and peritoneal adhesions were graded. RESULTS: The SPF group had no adhesions. Adhesions were increased similarly in the SP and LPF groups, and further increased in the LP group. Postoperative serum cytokine levels showed a similar pattern of increases. CONCLUSIONS: The presence of latex or powder on surgical gloves promoted increased adhesions. Serum cytokine levels correlated with the degree of adhesion formation. Strategies to use latex-free, powder-free gloves and/or limit cytokine expression may decrease peritoneal adhesions in the clinical setting.     

Collagen-PVP,a collagen synthesis modulator,decreases intraperitoneal adhesions

BACKGROUND: Adhesion formation in the peritoneal cavity is the most common cause of intestinal obstruction and secondary female infertility. A great effort has been dedicated to reduce adhesion formation because of the associated morbidity and its complications. MATERIALS AND METHODS: This study was designed as a before-after comparative trial and included 14 rabbits, with a weight between 300 and 500 g. All rabbits were appendectomized and 1 month later laparotomized to assess adhesion formation. Rabbits were randomized into two groups, Group I (control group), with no intervention, and Group II (experimental group), treated with an intraperitoneal sponge of collagen-polyvinylpyrrolidone (Clg-PVP). The laparotomy procedure was repeated 1 month later for a new assessment of adhesion formation and histological evaluation by H-E and Masson staining. RESULTS: Histological findings showed abundant infiltrate in the control group, which was mild in the experimental group. With the Masson stain the control group showed a significantly higher amount of collagen than the experimental group and the fibrous tissue was more compact. We found a mean number of adhesions of 3.29 +/- 1.98 for the control group, which decreased to 2.57 +/- 0.79 after the second laparotomy. For the experimental group the mean number of adhesions decreased from 1.86 +/- 0.90 to 0.71 +/- 0.49 after the second laparotomy, with no statistical difference between both groups before Clg-PVP application, but a significant statistical difference after the implantation of Clg-PVP (Student's t test; P < 0.001, two-tailed). CONCLUSION: Collagen-polyvinylpyrrolidone decreases the incidence and size of intraabdominal adhesions after secondary adhesion formation after appendectomy.     

Evaluation of sepramesh biosurgical composite in a rabbit hernia repair model

BACKGROUND: In cases such as incisional hernia repair, polypropylene mesh (PPM) can be exposed to the underlying viscera and cause adhesions to the mesh. In this study, a composite prosthesis that was designed to be less susceptible to adhesion formation than PPM was evaluated in a rabbit incisional hernia repair model. MATERIALS AND METHODS: A 5 x 7-cm full-thickness defect was created in the abdominal wall of 30 female New Zealand White rabbits. Ten animals each were repaired with PPM, Bard Composix (PP/ePTFE), or Sepramesh biosurgical composite-a polypropylene mesh coated on one side with chemically modified sodium hyaluronate and carboxymethylcellulose (HA/CMC). The animals were sacrificed after 28 days and the overall performance, including adhesion formation and tissue integration by histology and mechanical testing, was evaluated. RESULTS: In the Sepramesh group, there was a significant reduction in the percentage of surface area covered by adhesions and a significant increase in the percentage of animals with no adhesions compared to standard materials. The tissue integration strength and overall cellular response were similar in all groups. A partially remesothelialized peritoneal surface was often apparent overlying the Sepramesh implant. CONCLUSIONS: Sepramesh biosurgical composite effectively repaired abdominal wall defects in rabbits and reduced adhesion development to the mesh compared to the use of a PPM and a PP/ePTFE composite.     

Effects of intraperitoneal 4% icodextrin solution on the healing of bowel anastomoses and laparotomy incisions in rabbits

Objective Peri‐operative lavage and postoperative instillation of a 4% icodextrin solution reduces de novo formation and reformation of peritoneal adhesions following abdominal surgery. This experimental study evaluated the effects of 4% icodextrin treatment on the healing of bowel anastomoses and laparotomy incisions. Materials and methods Female New Zealand White rabbits (weight 2.21–2.77 kg) were randomised by ascending weight to one of 3 surgical treatments, each with 2 termination points (6 groups of 8 animals). The treatments were anastomotic bowel surgery alone or with lavage and postoperative instillation of either 4% icodextrin solution or Lactated Ringer's Solution (LRS). The solutions were coded A and B by the supplier, so that the study personnel were blinded to their identity. After the abdomen was opened, 30 ml of solution A or B was instilled and removed by aspiration prior to surgery. The ascending colon was then transected 5 cm aboral to the ileocaecal junction and the ends anastomosed. During surgery, 5 ml of the solution was applied 4 times at the surgical site, and a further 30 ml was administered and aspirated as a postoperative lavage. Just prior to closure of the abdominal wall, 50 ml of the solution was administered as a postoperative instillate. Duplicate treatment groups were terminated 7 and 21 days after surgery and the anastomotic sites inspected for adhesion and/or abscess formation. In 6 animals per group, an 8–12 cm length of colon including the anastomotic site was removed for measurement of bursting pressure, and a section of the abdominal wall including the incision line was tested for breaking strength. The other 2 animals per group provided tissue for histological analysis of wound healing at the bowel and incision sites. Results There was no significant difference between the 3 treatment groups for any parameter (P > 0.05). Compared with the surgical control at either day 7 or 21 after surgery, the administration of solutions A or B did not affect the formation of abscesses or adhesions, the bursting strength of the bowel, or the tear strength of the abdominal wall incision. Histological assessment of the quality of wound healing showed no differences between treatment groups in inflammatory cell infiltration, fibroblast density, blood vessel formation or collagen maturity. Conclusions The use of a 4% icodextrin solution for peri‐operative lavage and postoperative instillation in a rabbit model of bowel anastomotic healing did not result in any difference from either LRS treated or untreated surgical controls.     

Effect of Temporary Abdominal Closure on Colonic Anastomosis and Postoperative Adhesions in Experimental Secondary Peritonitis

Background The effect of relaparotomies and temporary abdominal closure on colonic anastomoses and postoperative adhesions is under debate. Methods In the experiments reported here, colonic anastomosis was constructed 24 hours after cecal ligation and puncture in rats that were divided into three groups of eight animals each. The abdomen was closed primarily in groups I and II, and a Bogota bag was used for abdominal closure in group III. At 24 hours following anastomosis, relaparotomy was performed only in group II and III rats, and the abdomen was closed directly in group II; after removal of the Bogota bag in group III animals, the abdomen was closed directly. On the fifth day of anastomotic construction, bursting pressures and tissue hydroxyproline content of the anastomoses, along with peritoneal adhesions, were assessed and compared. Results Mean anastomotic bursting pressures and hydroxyproline contents did not differ among the groups. Median adhesion scores were significantly higher in group III than the other two groups. Conclusions Relaparotomy and the type of temporary closure have no negative effect on anastomotic healing in rats with peritonitis. Temporary abdominal closure with a Bogota bag caused a significantly high rate of adhesions.     

Do bipolar scissors increase postoperative adhesions? An experimental double-blind randomized trial

AIM: The use of bipolar scissors (PowerStar) which has been suggested to reduce bleeding during surgical dissection, involves the theoretical risk for increasing intraperitoneal adhesions because of burn damages to the peritoneum secondary to bipolar electrocautery. MATERIAL AND METHOD: Thirty-six white new-Zealand rabbits have been included in a double-blind randomised trial to undergo a laparotomy using either a sharp scissors with on-demand monopolar coagulation or a bipolar scissors. Operatives procedures were standardised: midline laparotomy (5 cm), mobilisation of the right colon, incision of the colonic serosa without suture, incision of the colonic serosa with running sutures, incision of the mesentery. All these steps were performed by the same device according to the randomisation. Ten days later, the rabbits were killed. Adhesions were measured and scored according to the Zühlke classification by a surgeon who was not aware of the type of scissors used. Finally a pathological examination of adhesion was randomly performed. RESULTS: The two groups were similar for weight and sex-ratio. Two rabbits died before the tenth postoperative day (1 unknown aetiology and 1 evisceration). 34 rabbits were available for the study (18 in the "PowerStar" group and 16 in the control group). The results showed no significant difference between the groups for all measured endpoints (length and score of intraperitoneal and parietal adhesions). Nevertheless, pathological examination showed the burn damages to be less pronounced after using PowerStar. CONCLUSION: Bipolar scissors do not increase postoperative adhesions in the rabbit and probably induce less burn damages than monopolar cautery. The additional advantage i.e. the decrease adhesions formation, because of a less intraperitoneal bleeding, has not been observed in this randomised trial.     

Intraperitoneal transplantation of isologous mesothelial cells for prevention of adhesions.

OBJECTIVE: To study the effect of transplantation of mesothelial cells on the formation of adhesions after peritoneal abrasion. DESIGN: Animal study. SETTING: Teaching hospital, Germany. ANIMALS: 30 isologous eight-week old Lewis rats to allow for harvesting of the greater omentum from a separate group. INTERVENTIONS: The first group (n = 10) served as mesothelial cell donors. The other animals had laparotomy and induction of adhesions by standardised abrasion of the peritoneum. The trial group (n = 10) were given a suspension of 10(6) mesothelial cells/100 g body weight intraperitoneally and the control group (n = 10) an equal volume of culture medium. After 10 days the animals were killed. MAIN OUTCOME MEASURES: Measurements of the areas of adhesions by computer aided morphometry. RESULTS: The trial group developed a mean (SD) adhesion area of 122.7 (176.7) mm2, and the controls 310.5 (179.1) mm2. The corresponding medians (range) were 51.2 (0-547.1) and 274.3 (100.6-575.4). Transplantation of mesothelial cells resulted in a significant reduction in adhesion formation (Wilcoxon test, p<0.01). CONCLUSION: Intraperitoneal transplantation of mesothelial cells is an effective way of reducing the formation of adhesions.