Pretreatment with mineralocorticoid receptor blocker reduces intestinal injury induced by ischemia and reperfusion: involvement of inhibition of inflammatory response, oxidative stress, nuclear factor κB, and inducible nitric oxide synthase.

BACKGROUND: Spironolactone (Sp), a mineralocorticoid receptor antagonist, protects against the ischemia reperfusion (IR) injury of retina, kidney, heart, and brain. We aimed to investigate the effects of Sp on intestinal IR injury. METHODS: Male Wistar rats were randomly divided into: (1) a sham control group; (2) an IR control group, subjected to 30 min ischemia and 3 h reperfusion; (3) a group treated with Sp (20 mg/kg) for 3 d before the IR; and (4) a sham-operated control group treated with Sp (20 mg/kg). After the reperfusion, blood and intestinal tissue samples were collected to evaluate histopathologic state, neutrophil infiltration (by measuring myeloperoxidase activity), levels of the cytokines (tumor necrosis factor α, interleukin 1α [IL-1α], interferon γ, monocyte chemotactic protein-1, granulocyte macrophage-colony stimulating factor, and IL-4), malondialdehyde (MDA) and reduced glutathione contents, and immunohistochemical expressions of nuclear factor κB, inducible nitric oxide synthase (iNOS), and caspase-3. RESULTS: MDA content, myeloperoxidase activity, and plasma levels of tumor necrosis factor α, IL-1α, and monocyte chemotactic protein-1 were all elevated in IR, indicating the oxidative stress and local and systemic inflammatory response. Sp administration markedly reduced the MDA content and the cytokine levels. The pretreatment alleviated intestinal injury, neutrophil infiltration, and the expressions of caspase-3, iNOS, and NFκB. CONCLUSIONS: The results implicate that Sp may have a strong protective effect against the intestinal IR injury. The effect can be mediated via suppression of both systemic inflammatory response and apoptosis through amelioration of oxidative stress and generation of proinflammatory cytokines, iNOS, caspase-3, and nuclear factor κB. Therefore, mineralocorticoid receptor antagonism might be of potential therapeutic benefit in cases of intestinal IR damage.

Erythropoietin: a possible cytoprotective cytokine in acute necrotizing pancreatitis.

BACKGROUND/PURPOSE: Despite decades of research and clinical trials, a specific therapeutic treatment for acute pancreatitis (AP) has yet to be developed. The aim of the present study was to investigate the effects of erythropoietin on the severity of taurocolic acid-induced acute necrotizing pancreatitis. METHODS: Forty-seven male Wistar albino rats were randomized into seven experimental groups. In group I, animals were sham-operated (n = 5). In groups II, III, IV, IIepo, IIIepo, and IVepo, AP was induced by sodium taurodeoxycholate treatment (n = 7). In groups II, III, and IV, 1 ml normal saline and in groups IIepo, IIIepo, and IVepo, 1000 U/kg body weight erythropoietin (EPO) was administered intramuscularly immediately after the induction of AP. Animals were killed at 24, 48, and 72 h postoperatively. Histopathological and biochemical evaluations were performed. RESULTS: The serum levels of interleukin-6 (IL-6) and tissue levels of malondialdehyde were found to be significantly lower in EPO-administered groups when compared with the levels in groups without EPO treatment. The severity of pancreatic edema, acinar necrosis, inflammation, and perivascular infiltrate were reduced in all the EPO groups compared with the no-treatment groups. CONCLUSIONS: Our findings may reflect the possible cytoprotective effect of EPO in acute necrotizing pancreatitis.

Lipoma within inverted Meckel's diverticulum as a cause of recurrent partial intestinal obstruction and hemorrhage: a case report and review of literature.

Lipoma within an inverted Meckel's diverticulum presenting with hemorrhage and partial intestinal obstruction is an exceptional clinical entity. We report a case of 47-year-old male with a history of recurrent episodes of partial intestinal obstruction and melena due to a subserosal lipoma located in the base of an inverted Meckel's diverticulum. According to our knowledge, this is the first case of a lipoma within a Meckel's diverticulum giving rise to this clinical scenario without the existence of heterotrophic gastric or pancreatic tissues.

Neural cell adhesion molecule-180 expression as a prognostic criterion in colorectal carcinoma: feasible or not?

AIM: To evaluate the frequency of neural cell adhesion molecule (NCAM)-180 expression in fresh tumor tissue samples and to discuss the prognostic value of NCAM-180 in routine clinical practice. METHODS: Twenty-six patients (16 men, 10 women) with colorectal cancer were included in the study. Fresh tumor tissue samples and macroscopically healthy proximal margins of each specimen were subjected to flow-cytometric analysis for NCAM-180 expression. RESULTS: Flow-cytometric analysis determined NCAM-180 expression in whole tissue samples of macroscopically healthy colorectal tissues. However, NCAM-180 expression was positive in only one case (3.84%) with well-differentiated Stage II disease who experienced no active disease at 30 mon follow-up. CONCLUSION: As a consequence of the limited number of cases in our series, it might not be possible to make a generalisation, nevertheless the routine use of NCAM-180 expression as a prognostic marker for colorectal carcinoma seems to be unfeasible and not cost-effective in clinical practice due to its very low incidence.

Protective effects of erythropoietin against acute lung injury in a rat model of acute necrotizing pancreatitis.

AIM: To investigate the effect of exogenous erythro-poietin (EPO) administration on acute lung injury (ALI) in an experimental model of sodium taurodeoxycholate- induced acute necrotizing pancreatitis (ANP). METHODS: Forty-seven male Wistar albino rats were randomly divided into 7 groups: sham group (n = 5), 3 ANP groups (n = 7 each) and 3 EPO groups (n = 7 each). ANP was induced by retrograde infusion of 5% sodium taurodeoxycholate into the common bile duct. Rats in EPO groups received 1000 U/kg intramuscular EPO immediately after induction of ANP. Rats in ANP groups were given 1 mL normal saline instead. All animals were sacrificed at postoperative 24 h, 48 h and 72 h. Serum amilase, IL-2, IL-6 and lung tissue malondialdehyde (MDA) were measured. Pleural effusion volume and lung/body weight (LW/BW) ratios were calculated. Tissue levels of TNF-alpha, IL-2 and IL-6 were screened immunohistochemically. Additionally, ox-LDL accumulation was assessed with immune-fluorescent staining. Histopathological alterations in the lungs were also scored. RESULTS: The mean pleural effusion volume, calculated LW/BW ratio, serum IL-6 and lung tissue MDA levels were significantly lower in EPO groups than in ANP groups. No statistically significant difference was observed in either serum or tissue values of IL-2 among the groups. The level of tumor necrosis factor-alpha (TNF-alpha) and IL-6 and accumulation of ox-LDL were evident in the lung tissues of ANP groups when compared to EPO groups, particularly at 72 h. Histopathological evaluation confirmed the improvement in lung injury parameters after exogenous EPO administration, particularly at 48 h and 72 h. CONCLUSION: EPO administration leads to a significant decrease in ALI parameters by inhibiting polymorphonuclear leukocyte (PMNL) accumulation, decreasing the levels of proinflammatory cytokines in circulation, preserving microvascular endothelial cell integrity and reducing oxidative stress-associated lipid peroxidation and therefore, can be regarded as a cytoprotective agent in ANP-induced ALI.

Comparison between powdered gloves, powder-free gloves and hyaluronate/carboxymethylcellulose membrane on adhesion formation in a rat caecal serosal abrasion model.

OBJECTIVE: Intraabdominal adhesion formation and prevention is one of the major conflicts of modern surgery. We aimed to determine the effects of powdered gloves versus powder-free gloves and hyaluronate/carboxymethylcellulose membrane (H/CMCm) in a rat caecal serosal abrasion model. METHODS: Sixty wistar albino rats were subjected to a standardized lesion by caecal abrasion model. In group 1, the procedure was performed with sterile powdered gloves. In group 2, the procedure was performed with powder-free sterile gloves. The H/CMCm was applied directly to the abraded caecum in group 3. Formation of adhesions were determined on one half of the animals from each group on the 7th postoperative day, and on the other half on the 15th postoperative day. RESULTS: There was a statistically significant difference between the adhesion scores on day 7 and 15 in groups 1 and 2 (p = 0.005, p = 0.007). There was no significant difference in adhesion scores on day 7 and 15 in group 3 (p = 0.145). The mean adhesion score was significantly higher in group 1 (powdered glove group) than group 2 (powder-free glove group) and group 3 (powder-free glove plus H/CMCm) on postoperative day 7 (p = 0.001). However, no significant difference was found between groups regarding adhesion scores on postoperative day 15 (p = 0.607). The comparisons of group 2 versus group 3, both on postoperative day 7 (p = 0.051) was not statistically significant, whereas a significant difference was detected between group 1 versus group 2 and group 3 on postoperative day 7 (p = 0.013, p = 0.001). CONCLUSION: Our experiment shows that the use of powder-free gloves may be as beneficial as Seprafilm in preventing postoperative adhesion formation.

Clinical evaluation of submucosal colonic lipomas: decision making.

Even lipomas are the most common mesenchymal benign tumors of the gastrointestinal tract, symptomatic colonic presentation is rare. Herein, we evaluated four patients suffering from various size of colonic lipomas and approached by different therapeutic modalities.

Importance of identifying the course of the recurrent laryngeal nerve in total and near-total thyroid lobectomies.

In our clinic, near-total thyroidectomy is the principal surgical procedure performed for benign thyroid diseases. We conducted a single-institution study on 176 consecutive patients who underwent near-total thyroidectomy due to various thyroid diseases. We compared the incidence of recurrent laryngeal nerve injury between total and near-total thyroid lobectomy sides in each patient. Our hypothesis was that the incidence of recurrent laryngeal nerve injury after total thyroid lobectomy would be similar to that of near-total thyroid lobectomy when the course of the recurrent laryngeal nerve was identified during surgery. The temporary recurrent laryngeal nerve palsy rates on the total and near-total thyroid lobectomy sides were 3.9 per cent (7 of 176 nerves) and 2.2 per cent (4 of 176 nerves), respectively. The difference was not statistically significant. Permanent recurrent laryngeal nerve palsy did not occur in any of our patients. In conclusion, the incidence of recurrent laryngeal nerve injury in total versus near-total thyroid lobectomy is not different when the course of the recurrent laryngeal nerve is identified during surgery.

Medical haemostasis in acute hepatocyte injury and experimental liver trauma.

BACKGROUND: The aim of the present study was to test the effectiveness of aprotinin to reduce bleeding in liver resection of guinea pigs with acutely injured hepatocyte using intraperitoneal d(+)Galactosamine. METHODS: Thirty-two guinea pigs were divided equally into four groups. Group 1 was the control group. Group 2 received intraperitoneal D(+)galactosamine. Group 3 received intraperitoneal d(+)galactosamine prior to a standard liver resection. Group 4 received 10.000 KIU/kg aprotinin infusion via jugular catheter in 10 min prior to standard liver resection in pretreated animals with d(+)galactosamine. All of the measurements and surgical interventions were made 24 h after the administration of d(+)galactosamine. Bleeding amounts were recorded in groups 3 and 4 for 1 h by weighing the sponges placed into the abdomen. Liver function tests, histologic, haematologic and fibrinolytic parameters were measured. RESULTS: Hepatocyte injury and hyperfibrinolysis were seen at the end of 24 h after application of d(+)galactosamine in groups 2, 3, and 4. Statistically significant amounts of bleeding from the resected livers were observed in group 3 and 4. In group 4, the bleeding was reduced (P < 0.05) and fibrinolytic parameters were normalized (P < 0.05) with aprotinin infusion. CONCLUSIONS: Significant bleeding diathesis and hyperfibrinolysis occurred in groups 2, 3, and 4, which had hepatocyte injury proved with histopathologic and haematologic tests. Prothrombin time (PT) and partial thromboplastin time (aPTT) in groups 3 and 4 were fivefold higher than that in the control group (P = 0.0001). The bleeding tendency according to high PT and aPTT levels were continued with application of aprotinin while reduction of bleeding was seen. Parenchymatous organ haemorrhage in acute liver failure or hyperfibrinolytic conditions could be reduced significantly with aprotinin without procoagulant effect.

Near-total thyroidectomy could be the best treatment for thyroid disease in endemic regions.

HYPOTHESIS: Near-total thyroidectomy, on the basis of its low morbidity rate, is an appropriate treatment option in the surgical management of various thyroid diseases in an endemic region in Turkey. DESIGN: Single-institution study of patients with various thyroid diseases treated by means of near-total thyroidectomy within 2 years in an endemic region, with comparison of the results vs the complication rates of bilateral subtotal and total thyroidectomy reported in the literature. SETTING: Tertiary academic referral center. PATIENTS: One hundred fifty-two patients who underwent near-total thyroidectomy for various thyroid diseases. MAIN OUTCOME MEASURES: Surgical treatments of various benign thyroid diseases were compared according to the complication rates and the achievable benefits of the procedures. RESULTS: In our clinic, near-total thyroidectomy was the principal surgical procedure performed for benign thyroid disease. The temporary recurrent laryngeal nerve palsy rate with respect to the nerves at risk was 3.3% (10 of 304 nerves), whereas temporary hypoparathyroidism was 7.2% (11 of 152 patients). Neither permanent recurrent laryngeal nerve palsy nor permanent hypoparathyroidism occurred. In 1 patient, wound hematoma developed and required re-exploration. Seroma in another patient needed no medical or surgical intervention. Neither wound infection nor mortality were noted. CONCLUSIONS: Near-total thyroidectomy achieves a lower complication rate of hypoparathyroidism and a similar complication rate of recurrent laryngeal nerve palsy and recurrence when compared with the rates reported in the literature for total thyroidectomy. It is an effective and safe surgical treatment option for various benign thyroid diseases.

Comparison of the measurement methods of bursting pressure of intestinal anastomoses.

BACKGROUND/AIMS: This study was designed to determine whether there exists a difference between in vivo and in vitro measurements of bursting pressure (BP) of experimental intestinal anastomosis studied in Wistar-albino rats. METHODOLOGY: In the first group (n=8), the BP was measured using in vivo method without detaching the adhesions around the anastomosis. BP was determined with digital manometer, and then anastomotic region was removed to measure tissue hydroxyproline (HP) levels. In the second group (n=8), the BP was measured with in vitro method after the segment of intestine including the anastomosis was dissected and isolated. The isolated specimen was then submerged in a normal saline bath. BP was determined with a digital manometer and anastomotic region was removed to measure tissue HP levels. RESULTS: While HP value in the first group was 105.60 +/- 9.43 microg/mg dry tissue, it was found to be 121.11 +/- 16.26 microg/mg dry tissue in the second group and this difference was not statistically significant (p=0.195). The BP was determined as 240.71 +/- 11.65 mmHg in the first group, 144.71 +/- 16.41 mmHg in the second group and the difference was statistically significant (p=0.002). The anastomotic resistances to intraluminal pressure were found to be statistically different whereas tissue HP levels were normal between the groups. CONCLUSIONS: These results make us consider that mechanical changes occur about the isolated anastomotic line and dissection of adhesions weakens the anastomosis.

Comparison of the experimental intestinal anastomoses performed by different surgeons.

BACKGROUND/AIMS: This study was designed to determine the effects of different surgeons on the experimental anastomosis studied in rats. METHODOLOGY: Sixteen Wistar-albino rats were equally separated into two groups. The rats operated on by the first surgeon were coded Group 1 and operated on by the other surgeon were coded Group 2. Both surgeons were trained on the gastrointestinal surgery. The procedure of the study were standardized and dictated to the surgeons. Bursting pressure and tissue hydroxyproline content were determined as parameters of the anastomotic strength and healing on the seventh day postoperatively. RESULTS: The bursting pressures were measured with a digital manometer and anastomotic lines were removed to measure tissue hydroxyproline level. While hydroxyproline value in the first group was 105.60 +/- 9.43 microg/mg dry tissue, it was found to be 104.02 +/- 17.26 microg/mg dry tissue in the second group and this difference was not statistically significant (p=0.521). The bursting pressure was determined as 240.71 +/- 11.65 mmHg in the first group, 190.75 +/- 14.09 mmHg in the second group and the difference was statistically significant (p=0.002). The anastomotic resistances to intraluminal pressure were found statistically different whereas tissue hydroxyproline levels were normal between the groups. CONCLUSIONS: These results make us to consider mechanical differences occur related to the surgeons in the studies performed with the same technical detail.

Enoxaparin-associated giant retroperitoneal hematoma in pulmonary embolism treatment.

CONTEXT: Retroperitoneal hematoma may usually occur as a result of trauma. A life threatening retroperitoneal hematoma is not expected complication of anticoagulation treatment and rarely reported. Low molecular weight heparins (Enoxaparin) which are used as effective and safe medicine in the venous thromboemboly treatment have some major complications such as hematomas of different organs. We aim to present a giant spontaneous retroperitoneal hematoma after anticoagulant treatment of pulmonary embolism with enoxaparin. CASE REPORT: A 73-year-old male patient with the diagnosis of pulmonary embolism underwent anticoagulant treatment (enoxaparin). In the second day of admission, the patient had an episode of abdominal and back pain. Abdominal ultrasonography and computerized tomographic scan revealed a giant retroperitoneal hematoma. Enoxaparin treatment was then stopped and the supportive treatment was started. In the following days, hemoglobin levels returned to normal and a control CT revealed regression of hematoma size. CONCLUSION: The anticoagulant treatment with enoxaparin may lead to severe hematomas. Therefore, the clinical suspicion is required especially in elderly patients and patients with impaired renal function for retroperitoneal hematoma, when they suffer from acute abdominal pain.

CD24 and galectin-1 expressions in gastric adenocarcinoma and clinicopathologic significance.

CD24 and galectin-1 expression in gastric adenocarcinoma and their clinicopathologic significance remained largely unknown. We aimed to evaluate expressions and staining intensities of CD24 and galectin-1 in gastric adenocarcinoma and to investigate the interrelation with clinicopathologic parameters including survival. 93 cases with gastric adenocarcinoma were reevaluated histopathologically and immunohistochemistry was performed with antibodies against CD24 and galectin-1. Staining intensities of both markers in tumor cells and staining intensity of galectin-1 in tumor-associated stromal cells were scored semiquantitatively. The relationship between expression and staining intensity of CD24 and galectin-1 and clinicopathologic variables were assessed. CD24 staining intensity was associated with lymphovascular invasion (p = 0.007), serosal invasion (p = 0.001), stage (p = 0.001) and lymph node metastasis (p = 0.005). Galectin-1 staining intensity in tumor-associated stromal cells was associated with tumor location (p = 0.031), lymphovascular invasion (p = 0.001), perineural invasion (p = 0.001), serosal invasion (p = 0.001), differentiation (p = 0.003), stage (p = 0.001) and lymph node metastasis (p = 0.001). Staining intensity of CD24 (p = 0.019) and gal-1 (p = 0.018) were associated with patient survival. Staining intensity of CD24 in tumor cells and galectin-1 in tumor-associated stromal cells were related with certain clinicopathologic variables. Our findings suggest that these markers are independent prognostic indicators of poor survival and may serve as useful targets for novel therapies.

Fournier's Gangrene after Open Hemorrhoidectomy without a Predisposing Factor: Report of a Case and Review of the Literature.

Fournier's gangrene (FG) is a fatal synergistic infectious disease with necrotizing fasciitis of the perineum and abdominal wall along with the scrotum and penis in men and vulva in women. An unpredictable case of FG two weeks after open hemorrhoidectomy in a previously healthy 55-year-old male is described. Full-thickness patchy skin necrosis of the perianal, perineal and scrotal region associated with rectal perforation was detected on admission. Prompt radical debridement together with aggressive fluid resuscitation and broad-spectrum antibiotic administration was initiated. Because of rectal involvement, diverting sigmoid colostomy was fashioned. The patient survived after two additional local debridements. Nevertheless, loss of sphincter function due to massive muscle destruction led to permanent colostomy. Our case together with others reported in the literature illustrates that, although rare, FG after open hemorrhoidectomy represents a life-threatening complication to otherwise healthy patients. The development of fever and urinary retention should draw the attention of the surgeon, even if the presentation is delayed. The current literature only briefly mentions the potential risk of FG after such a common surgical procedure. However, devastating complications occur more often than anticipated. This disastrous complication without predisposing factor is discussed along with a literature review.

Does sildenafil reverse the adverse effects of ischemia on ischemic colon anastomosis: yes, 'no'.

INTRODUCTION: Sildenafil may lead an improvement in anastomotic healing of ischemic left colon anastomosis. METHODS: Thirty-six male Wistar albino rats were randomized into four experimental groups (n=9 in each group). In group 1, a well-perfused left colonic segment was transected, and free ends were anatomosed. In groups 2, 3 and 4 animals underwent a standardized surgical procedure to induce ischemic left colon anastomosis. Group 2 animals received only tap water. In groups 3 and 4 animals received 10mg/kg/body-weight and 20mg/kg/body-weight sildenafil, single dose a day during 4 days, respectively. Rats were sacrificed on day 4 following operation. Anastomotic integrity, intra-peritoneal adhesion scores, anastomotic bursting pressures and tissue hydroxyproline levels were recorded. Histopathological examination of the anastomosis was also performed. RESULTS: There was no statistically significant difference among groups with respect to anastomotic integrity (p=0.142) but ischemia decreased the anastomotic bursting pressure. The mean bursting pressure values were 78.8+/-24.1, 43.3+/-26, 55.1+/-32.4, and 43.3+/-20.4 in groups 1, 2, 3, and 4, respectively. Group 1 had the highest values whereas; there was no statistically significant difference between groups 1 and 3. There was no statistically significant difference among groups 2, 3, and 4 with respect to tissue hydroxyproline levels, adhesion scores and the Chiu scores. The highest inflammatory cell presence in the granulation tissue was detected in group 2, whereas the lowest was detected in group 4 (p=0.0001). The highest fibroblast infiltration in the granulation tissue was detected in group 1 (p=0.045). DISCUSSION: Our results showed that 10mg/kg sildenafil decreased the adverse effects of ischemia on the healing of ischemic left colon anastomosis. Additional investigations are needed to confirm the effects of phosphodiesterase-5 inhibitors in ischemic colon anastomosis models.

Effect of 2-octyl-cyanoacrylate on ischemic anastomosis of the left colon.

INTRODUCTION: 2-octyl-cyanoacrylate may be a good alternative in ischemic colon anastomosis without impairment of tissue perfusion. METHODS: Forty male Wistar albino rats were randomized into four experimental groups (n = 10 in each group). In group 1 (control), a well-perfused left colonic segment was transected, and free ends were anastomosed by propylene sutures. In groups 2, 3, and 4, the animals underwent a standardized surgical procedure to induce ischemic left colon anastomosis. In group 2, an end-to-end anastomosis was created using six interrupted 6-0 polypropylene sutures between ischemic edges. In group 3, after approximating the mesenteric and antimesenteric edges of the anastomosis with two 6-0 polypropylene sutures, 2-octyl-cyanoacrylate was applied between the edges. In group 4, anastomosis was created by the same technique as described in group 2, and additionally 2-octyl-cyanoacrylate was applied on suture line. Rats were killed on day 4 following operation. Anastomotic integrity, intraperitoneal adhesion scores, anastomotic bursting pressures, and tissue hydroxyproline levels were recorded. Histopathological examination of the anastomosis was also performed. RESULTS: There were no statistically significant differences among groups with respect to anastomotic integrity (p =.142). The mean bursting pressure values were 81.1 +/- 23.83, 43.3 +/- 26.06, 15.8 +/- 11.3, and 17.6 +/- 18.02 in groups 1, 2, 3, and 4, respectively. There were no statistically significant differences among groups 2, 3, and 4 with respect to tissue hydroxyproline levels and bursting pressure levels. The highest adhesion scores were observed in groups 3 and 4. DISCUSSION: 2-octyl cyanoacrylate does not have additional advantages in the healing of experimental ischemic colon anastomosis.

The Janeway gastrostomy tube for recurrent gastric intubations: a novel and simple animal model.

Access to the gastric lumen can be achieved by different methods. Orogastric tubes and tube gastrostomies are frequently used but these routes have some disadvantages when recurrent gastric intubations or infusions are concerned. The Janeway gastrostomy tube is a simple-to-perform procedure and can serve as an excellent way to reach the gastric lumen of animals. It is also possible to insert large caliber devices such as cameras to examine the gastric lumen. Plugging of the pylorus is also possible with Fogarty catheters either blind or under radiological guidance. The Janeway gastric tube seems to be useful for long-lasting gastrointestinal procedures, for example gastric cancer studies.

The effect of sildenafil on an animal model for ischemic colitis.

INTRODUCTION: Sildenafil both enhances vasodilatation by relaxing the smooth muscle in the vessels and inhibits platelet aggregation. We have therefore examined the potential benefits of sildenafil on an animal model for ischemic colitis (IC). METHODS: Twenty-eight female Wistar albino rats weighing 250-300 g were randomized into three experimental groups as follows: in Group 1, animals were sham operated (n = 8) and received tap water; in Groups 2 and 3, the rats underwent a standardized surgical procedure to induce IC (n = 10 in each group). Group 2 animals served as the controls, receiving only tap water, while Group 3 animals received 10 mg/kg sildenafil per day as a single dose for a 3-day period. All animals were sacrificed 72 h after devascularization. To determine the severity of the ischemia, we scored the macroscopically visible damage, measured the ischemic area and scored the histopathology. Tissue malondialdehyde levels were also evaluated. RESULTS: The mean area of ischemic changes were 116.80 +/- 189.93 and 0.55 +/- 1.01 mm2 in Group 2 and 3 animals, respectively (p = 0.0001), while the macroscopically mean visible damage score decreased to 0.66 +/- 0.70 (p = 0.0001) for Group 3 animals. The Chiu scores were 0.00, 3.80 +/- 0.91 and 2.66 +/- 1.00 in Group 1, 2 and 3 animals, respectively. There was a statistically significant difference between Group 2 and 3 animals (p = 0.017). CONCLUSIONS: Our findings support the view that sildenafil leads to a improvement in IC due to its well-known effects on the vascular smooth muscle and on the microcirculatory hemodynamics.