Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of pretreatment with FK506 on renal ischemia and reperfusion (I/R) injury was investigated using a rat model. Animals were assigned to one of two groups (20 rats each). Group 1 animals (controls) received 0.5 ml saline while group 2 animals received FK506 (0.3 mg/kg), administered intravenously 24 hr prior to the induction of renal ischemia. A 60-min period of ischemia of the right kidney was induced, and upon reperfusion a left nephrectomy was performed. Blood samples for estimation of BUN, creatinine, and tumor necrosis factor were collected on days 0 (preischemia), 1, 2, 3, 5, 7, and 10 (postischemia). Rats were sacrificed after day 10 and renal tissue was examined histologically. All animals survived the ischemic episode. FK506 pretreatment significantly reduced the serum levels of BUN (P less than 0.02), creatinine (P less than 0.02), and TNF (P less than 0.05) as compared with that seen in controls. Histologically, at day 10, the kidneys showed the expected sequelae of prior renal I/R with various degrees of tubular damage. However, no objective differences were evident between the two groups. Based upon these data, it can be concluded that (1) FK506 pretreatment ameliorates the functional renal injury associated with I/R, (2) renal ischemia induces the release of TNF, and (3) FK506 pretreatment results in a significant inhibition of TNF production. These data suggest that the release of TNF may be responsible for the increasing of BUN and creatinine levels seen after renal I/R and that pretreatment of renal donors with FK506 may improve renal function in the immediate post-transplant period.
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PMID:The protective effect of FK506 pretreatment against renal ischemia/reperfusion injury in rats. 137 48

The present study was designed to elucidate the effect of FK506 on 90 min of warm ischemia of the liver and reperfusion in 30 dogs. Three groups of animals were studied. Group 1 animals received FK (0.15 mg/kg/day) for three days prior to the ischemia and group 2 animals got 2 ml of saline solution for three days instead of FK and were considered controls. In group 3 FK (0.15 mg/kg/day) was injected immediately upon reperfusion and two days thereafter. Evaluation of the effectiveness of the drug was monitored by measuring the serum activities of AST, ALT, LDH, serum total bilirubin, malondialdehyde, and by histopathological examinations of the liver specimens and survival of the animals for 7 days after reperfusion. The 7 day survival of the animals in group 1 (80%) was significantly (P < 0.05) improved compared with those in group 2 (30%) and group 3 (20%). The serum activities of AST, ALT, and LDH and total bilirubin were significantly lower in group 1 than in group 2 and group 3. FK pretreatment significantly prevented hepatocellular necrosis and neutrophilic infiltration in group 1 in comparison with those in group 2 and group 3. Although the malondialdehyde level in hepatic venous blood was relatively lower in group 1, this difference was not statistically significant. Three days FK pretreatment prevented hepatocellular injury and enzyme leakage after 90 min of hepatic ischemia, whereas FK treatment immediately upon reperfusion failed to do so. In conclusion, donor organ pretreatment with FK may become a promising strategy for improved allograft survival in liver transplantation.
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PMID:The salutary effect of FK506 in ischemia-reperfusion injury of the canine liver. 138 88

Experimental diabetes in rodents has been successfully treated by implantation of isolated islets using a syngenic system (Lewis rats). It is possible to reverse all diabetic symptoms of the animals and to prevent late complications in kidney, eye and nervous system. Although isolated islets are highly immunogenic in an allogenic system immuno-alteration techniques have been developed and succeeded in longterm survival after culture at low temperature (24 degrees C), UV-irradiation, cryopreservation, pretreatment with Ia-antibodies etc. Islet transplantation in larger animals and in man up to now has been less successful. Although in a few studies longterm survival of canine islets has been observed, other groups were less successful using dogs and pigs in auto- or allo-transplantation. In man there are reports from various institutions during the last fifteen years using adult or fetal islet material. Only in a few instances the patients came off insulin for some weeks or months. The reasons for this failure are probably manifold: low number of islets, impurity, long ischemia time before isolation, transplantation to inappropriate sites, impairment of engraftment in longterm diabetic recipients and recurrence of autoimmunity in transplanted islets. Further studies are necessary to overcome these barriers. Recent observations using a higher number of islets (> 500,000) and new immunosuppressive drugs (FK506) seem to be promising.
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PMID:Islet transplantation: clinical and experimental. 149 Jun 85

Isolated segments of cat small intestine were subjected to 3 hr of ischemia followed by 1 hr reperfusion (I/R). Mucosal biopsies were obtained for measurement of myeloperoxidase (MPO) activity, an index of tissue neutrophil count, and leukotriene B4 (LTB4) production. Animals were pretreated with either cyclosporin A (CsA) or FK506, which are potent immunosuppressants. Both agents significantly attenuated the neutrophil infiltration induced by I/R. FK506, but not CsA, reduced the elevated mucosal LTB4 production normally observed following reperfusion. The results of this study suggest that FK506 and CsA may be important agents in modulating neutrophil infiltration in acute inflammatory conditions.
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PMID:Effects of cyclosporin A and FK506 on ischemia/reperfusion-induced neutrophil infiltration in the cat. 171 12

The mechanism by which FK506 (FK) prevents hepatic injury induced by ischemia/reperfusion was studied. Adult Sprague-Dawley rats were subjected to 60-min normothermic liver ischemia. Animals were divided into two groups: group I, controls, saline vehicle treatment; group II, FK treatment. FK (1 mg/kg/day, p.o.) was given for 4 consecutive days prior to inducing ischemia. In addition to a survival study, plasma levels of endotoxin and serum activities of tumor necrosis factor-alpha (TNF) and aspartate aminotransferase (AST) were assessed in the blood collected from suprahepatic vena cava. Results showed: (1) FK therapy significantly improved 7-day survival (80.0%) compared with nontreated animals (50.0%, p < 0.05); (2) both TNF and endotoxin were elevated following reperfusion, reaching maximum values at 3 h after reperfusion (217.0 +/- 40.6 and 280.5 +/- 31.4 pg/ml, respectively, in the control; mean +/- SEM), and (3) serum activities of TNF and AST following reperfusion were substantially suppressed with FK treatment, whereas FK did not reduce the rise in endotoxin. These findings suggest that suppression of TNF production in response to endotoxemia might account at least in part for the protective effect of FK against ischemia-induced hepatic injury.
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PMID:Evidence that FK506 alleviates ischemia/reperfusion injury to the rat liver: in vivo demonstration for suppression of TNF-a production in response to endotoxemia. 751 91

Previous clinical evaluation of FK506 in renal transplantation has demonstrated equivalent patient and graft survival when compared with cyclosporine-based regimens. However, lower steroid and anti-hypertensive mediation requirements and lower serum cholesterol levels have been seen in patients receiving FK506. In August, 1991, a prospective, randomized trial was begun, comparing FK506/prednisone with FK506/azathioprine/prednisone. Two-hundred-and-four adults were entered into this trial between August 1, 1991, and October 11, 1992. The mean recipient age was 43.8 +/- 13.7 years, with a range of 17.6-78.0 years. Sixty-one (30%) recipients received a 2nd, 3rd or 4th transplant, while 35 (17%) had a PRA greater than 40% at the time of transplant. Thirty-three (16%) of the transplants were in recipients over 60 years of age, Thirteen percent of the kidneys were from living donors; 13% of the cadaveric kidneys were from pediatric donors less than 3 years of age and were transplanted en bloc. The mean cold ischemia time was 31.4 +/- 8.4 hours, and the mean donor age was 34 +/- 2.10 years, with a range from 4 months to 75 years. With a mean follow-up of 9 +/- 4 months, the 1-year actuarial patient survival is 93%; for the two-drug group it is 95%, and for the three-drug group it is 91% (p = NS). One-year actuarial graft survival is 86%; in the two-drug group it is 90%, while in the three-drug group it is 82% (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:A prospective, randomized trial of FK-506 in renal transplantation--a comparison between double- and triple-drug therapy. 753 75

A group of 204 adult patients was entered into a prospective, randomized trial comparing FK506/prednisone with FK506/azathioprine/prednisone after renal transplantation between August 1, 1991 and October 11, 1992. The purpose of the study was to see if the addition of azathioprine would reduce the incidence of rejection and improve graft survival. The recipient population was unselected, with 61 (30%) patients undergoing retransplantation, 37 (18%) having a panel-reactive antibody greater than 40%, and 33 (16%) over 60 years of age. The mean recipient age was 43.8 +/- 13.7 years (range 17.6-78). The mean donor age was 34.0 +/- 20.1 years (range 0.3-75); 13% of the cadaveric kidneys were from pediatric donors less than 3 years of age and were transplanted en bloc. The mean cold ischemia time was 31.4 +/- 8.4 hr. Living donors were the source of 13% of the kidneys. The mean follow-up was 22 +/- 4 months (range 12-29). Overall one-year actual patient survival was 94%. Overall one-year actual graft survival was 87%. Patients starting on double therapy had a one-year actual patient survival of 96% and a one-year actual graft survival of 92%. Patients starting on triple therapy had a one-year actual patient survival of 91% (P = ns compared with double therapy), and a one-year actual graft survival of 82% (P < 0.02, compared with double therapy). Overall results with first cadaver transplants included a one-year actual patient survival of 94% and one-year actual graft survival of 88%, with no differences between double and triple therapy. The overall incidence of rejection was 48%, with 54% in the double therapy group and 41% in the triple therapy group (P < .07). The incidence of steroid-resistant rejection requiring antilymphocyte therapy (OKT3 or ATGAM) was 13%, and was not different between the double and triple therapy groups. The mean serum creatinine was 1.8 +/- 0.8 mg/dl. The mean BUN was 33 +/- 21 mg/dl, with no significant difference between the therapy groups. The mean serum cholesterol was 192 +/- 49 mg/dl. A total of 56% of the patients are off prednisone, and 35% of the patients are not taking any antihypertensive medications. Other complications included cytomegalovirus--14%; new-onset diabetes--16% (half of which was reversible); and posttransplant lymphoproliferative disorder--1%.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:A prospective randomized trial of FK506-based immunosuppression after renal transplantation. 753 43

The protective effect of FK506 on hepatocytes against ischemia and reperfusion injury was examined by evaluating the following: the high energy phosphorus metabolism obtained using 31P magnetic resonance spectroscopy (31P-MRS) and the tissue blood flow of the liver in ischemia and the reperfusion process, mitochondrial glutamic oxaloacetic transaminase (m-GOT) and glutamic pyruvic transaminase (GPT), the survival rates of the animals, a histological study and immunohistological staining for intercellular adhesion molecule-1 (ICAM-1) in the liver after ischemia. The rats were treated with FK506 1 mg/kg/day i.m. for 4 days before testing. Ischemia was induced by clamping the hepatoduodenal ligament for 30 min. In 31P-MRS, the recovery of the hepatic energy status after ischemia, evaluated by beta-ATP/inorganic phosphate (Pi), was significantly better in the FK506 group. It also coincided with the recovery of tissue blood flow monitored with a laser Doppler flowmeter. In the histological examination, the congestion observed in the periportal region of the control group was mild, while there was less induction of ICAM-1 in the endothelial cells of the portal veins and hepatic veins in the FK506 group. From these findings, we concluded that FK506 had a protective effect on hepatocytes against warm ischemia and reperfusion injury, and the mechanism for this could partially be attributed to improved tissue blood flow after ischemia by the modulation of immunological events.
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PMID:The effect of FK506 on warm ischemia and reperfusion injury in the rat liver. 753 46

In order to study further whether a relationship exists between the extent of ischemia-preservation-reperfusion injury (IPRI) and acute rejection (AR) events in liver allografts, we retrospectively reviewed 213 consecutive cyclosporine-treated patients who received their first liver allograft between 1/1/93 and 12/31/93. Of these, 178 fulfilled the study inclusion criteria. The extent of IPRI was assessed by the peak value of aspartate aminotransferase (ASTmax) observed within the first 72 hr posttransplant. For the purpose of univariate analysis, categorical classification of recipients was done based upon ASTmax as follows: group 1, ASTmax < 600 IU/L (n = 43); group 2, ASTmax 600-2000 IU/L (n = 86); and group 3, ASTmax > 2000 IU/L (n = 49). For multivariate analysis, stepwise Cox regression was performed with age, ASTmax, and UNOS status as covariates. At a median follow-up of 271 days there were no statistically significant differences between groups with respect to the incidence of a first episode of AR (47%, 55%, 51%, respectively, P = NS), the timing of AR (respective medians, 9, 10, and 10 days, P = NS), or the proportion of patients treated with OKT3 (9%, 20%, 12%, respectively, P = NS) or converted to FK506 (16%, 12%, 10%, P = NS). Cox regression confirmed the lack of an independent association between the extent of IPRI and any of these outcomes. We conclude that in UW-preserved, cyclosporine-treated primary liver allografts, no correlation exists between the extent of IPRI and the incidence, timing, severity, or refractoriness of clinically defined AR events.
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PMID:Lack of correlation between the magnitude of preservation injury and the incidence of acute rejection, need for OKT3, and conversion to FK506 in cyclosporine-treated primary liver allograft recipients. 757 Sep 50

We investigated the cardioprotective effect of FK506, a newly developed immunosuppressive agent, on ischemia-reperfusion-induced myocardial damage and the inhibitory effect of FK506 on superoxide radical formation by neutrophils. Open-chest anesthetized dogs were divided into two groups: group 1, 2-h occlusion of the coronary artery followed by 1-h reperfusion; and group 2, 2-h occlusion followed by 1-h reperfusion with preadministration of FK506 (0.5 mg/kg). After reperfusion, heart mitochondria were prepared from the normal and reperfused areas and mitochondrial function and mitochondrial GSH (the reduced form of glutathione) and GSSG (the oxidized form of glutathione) concentrations were measured. In addition, neutrophils were collected from normal healthy dogs, and the inhibitory effect of FK506 on superoxide radical formation by neutrophils was also investigated. One-hour reperfusion after 2-h coronary occlusion induced significant mitochondrial dysfunction associated with a marked depletion of mitochondrial GSH concentration. FK506 reduced mitochondrial dysfunction, depletion of mitochondrial GSH concentration, and development of reperfusion arrhythmias. FK506 also reduced stimulant-induced superoxide radical formation by normal neutrophils dose dependently. Radical scavenging activity decreased in association with reperfusion, and FK506 reduced superoxide radical formation by neutrophils, which might contribute to lessening ischemia-reperfusion damage.
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PMID:Protective effect of FK506 on ischemia/reperfusion-induced myocardial damage in canine heart. 768 7


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