Influence of buprenorphine analgesia on post-operative recovery in two strains of rats.

The objective of this study was to establish an effective post-operative analgesic regimen for Sprague-Dawley (SD) and Dark Agouti (DA) rats. Buprenorphine (0.01 or 0.05 mg/kg), a partial mu opioid agonist, was administered subcutaneously immediately on completion of a standardized surgical procedure, involving anaesthesia, laparotomy and visceral manipulation. Two of the four treatment groups and the saline control group received a second injection 9 h later. Behavioural observations by three independent observers provided no information in assessing pain in this model. All rats lost weight, consumed less food and water after surgery. On the first day, both SD and DA rats receiving buprenorphine lost less weight than untreated control groups. Using weight loss as an efficacy criterion, low-dose buprenorphine, given once or twice, provided effective analgesia in SD rats. A higher single dose provided no additional benefit and a second dose was detrimental, reducing body weight and food intake. In DA rats, the high dose, given twice, appeared to be more effective than the lower dose. All DA cage cohorts consumed < 10% pre-operative food despite buprenorphine treatment, suggesting a higher dosage may be necessary. However, all SD and 80% DA rats who received no buprenorphine gained body weight on the second day, whereas most of the buprenorphine-treated rats continued to lose weight for another 2 days, despite increased food consumption by both strains. Buprenorphine may adversely affect intestinal function over a number of days due to its enterohepatic circulation; this effect may be more severe in DA rats. Adverse metabolic effects of buprenorphine and other opioids may preclude their use in the future if it can be shown that non-steroidal anti-inflammatory drugs (NSAIDs) provide equally effective analgesia.     

Energy storage and cytokine response in patients undergoing liver transplantation

Overproduction of pro-inflammatory cytokines during surgery has been known to exert tissue-damaging and lethal effects on the host. Hypermetabolism-associated malnutrition, a common feature of patients with end-stage liver diseases, is related to the presence of a systemic inflammatory response, as reflected by enhanced levels of proinflammatory cytokines. The present study was designed to evaluate energy status of 29 liver transplant recipients, and to assess the relation of energy storage to post-operative cytokine response. The glycogen contents of the graft, and the recipient's abdominal muscle and old liver were measured. The plasma concentrations of tumour necrosis factor alpha, interleukin 1beta, interleukin 6, lactate, pyruvate and total ketone bodies were determined during and after surgery. In undernourished patients, ketone bodies seemed to be the major fuel available to muscle. The concentration of ketone bodies decreased rapidly after the incision, and remained at a low level after reperfusion. These patients had higher plasma levels of lactate/pyruvate ratio and aromatic amino acids during the anhepatic phase, followed by an exaggerated response of cytokines. Depletion of energy storage of the recipients may be involved in the deterioration of peri-operative energy metabolism and the exaggerated post-operative cytokine response.     

Protein F-induced immune tolerance in liver transplantation in rats

Liver-specific protein F is commonly used in liver transplantation studies for its allograft immunogenicity. The objective of this study was to investigate immune tolerance induced by protein F in liver transplantation in rats. Healthy inbred male Wistar and Sprague–Dawley (SD) rats were used in this study. The transplant recipient rats were randomly divided into three groups. The SD rats transplanted with liver tissues from SD rats or Wistar rats were defined as intragraft control group (Group A) or acute reaction group (Group B), respectively. The SD rats that received thymic administration of 4 mg protein F 1 week prior to transplantation with livers from Wistar rats were defined as protein F interference group (Group C). Kamada’s two-cuff technique was utilized in the liver transplantation surgeries. The postoperative general condition, transplantation survival time, pathological examination, and serum IFN-γ level (quantified by ELISA) were recorded and compared to evaluate the immune response and outcomes in the recipient rats after liver transplantation. Group A rats exhibited good postoperative condition and prolonged survival (median survival time was 92 days). In contrast, Group B rats lost body weight rapidly after liver transplantation, and died starting at day 12 (median survival time was 15 days). Compared to Group B, Group C rats showed significantly longer survival (medium survival time was 71 days). Our findings indicate that protein F is an important transplantation antigen with allograft immunogenicity, which could successfully induce immune tolerance in liver transplantation.     

Analgesic effects of tramadol, carprofen or multimodal analgesia in rats undergoing ventral laparotomy

In this study, the authors evaluated the analgesic efficacy of tramadol (an opioid-like analgesic), carprofen (a nonsteroidal anti-inflammatory drug) and a combination of both drugs (multimodal therapy) in a rat laparotomy model. The authors randomly assigned rats to undergo either surgery (abdominal laparotomy with visceral manipulation and anesthesia) or anesthesia only. Rats in each group were treated with tramadol (12.5 mg per kg body weight), carprofen (5 mg per kg body weight), a combination of tramadol and carprofen (12.5 mg per kg body weight and 5 mg per kg body weight, respectively) or saline (anesthesia control group only; 5 mg per kg body weight). The authors administered analgesia 10 min before anesthesia, 4 h after surgery or (for the rats that received anesthesia only) anesthesia and 24 h after surgery or anesthesia. They measured locomotor activity, running wheel activity, feed and water consumption, body weight and fecal corticosterone concentration of each animal before and after surgery. Clinical observations were made after surgery or anesthesia to evaluate signs of pain and distress. The authors found that carprofen, tramadol and a combination of carprofen and tramadol were all acceptable analgesia regimens for a rat laparotomy model.     

Analgesic efficacy of orally administered buprenorphine in rats

The analgesic effect of orally administered buprenorphine was compared with that induced by a standard therapeutic injected dose (0.05 mg/kg of body weight, s.c.) in male Long-Evans rats. Analgesia was assessed by measuring pain threshold, using the hot-water tail-flick assay before and after administration of buprenorphine. The results suggest that a commonly used formula for oral buprenorphine in flavored gelatin, at a dose of 0.5 mg/kg, does not increase pain threshold in rats. Instead, oral buprenorphine doses of 5 and 10 mg/kg were necessary to induce significant increases in pain threshold. However, these doses had to be administered by orogastric infusion because the rats would not voluntarily eat flavored gelatin containing this much buprenorphine. The depth of analgesia induced by these infused doses was comparable to that induced by the clinically effective s.c. treatment (0.05 mg/kg).     

Outcomes of patients with benign liver diseases undergoing living donor versus deceased donor liver transplantation

Background/Aims

The number of people undergoing living donor liver transplantation (LDLT) has increased rapidly in many transplant centres. Patients considering LDLT need to know whether LDLT is riskier than deceased donor liver transplantation (DDLT). The aim of this study was to compare the outcomes of patients undergoing LDLT versus DDLT.

Methods

A total of 349 patients with benign liver diseases were recruited from 2005 to 2011 for this study. LDLT was performed in 128 patients, and DDLT was performed in 221 patients. Pre- and intra-operative variables for the two groups were compared. Statistically analysed post-operative outcomes include the postoperative incidence of complication, biliary and vascular complication, hepatitis B virus (HBV) recurrence, long-term survival rate and outcomes of emergency transplantation.

Results

The waiting times were 22.10±15.31 days for the patients undergoing LDLT versus 35.81±29.18 days for the patients undergoing DDLT. The cold ischemia time (CIT) was 119.34±19.75 minutes for the LDLT group and 346±154.18 for DDLT group. LDLT group had higher intraoperative blood loss, but red blood cell (RBC) transfusion was not different. Similar ≥ Clavien III complications, vascular complications, hepatitis B virus (HBV) recurrence and long-term survival rates were noted. LDLT patients suffered a higher incidence of biliary complications in the early postoperative days. However, during the long-term follow-up period, biliary complication rates were similar between the two groups. The long-term survival rate of patients undergoing emergency transplantation was lower than of patients undergoing elective transplantation. However, no significant difference was observed between emergency LDLT and emergency DDLT.

Conclusions

Patients undergoing LDLT achieved similar outcomes to patients undergoing DDLT. Although LDLT patients may suffer a higher incidence of early biliary complications, the total biliary complication rate was similar during the long-term follow-up period.     

Reduction of isoflurane MAC with buprenorphine and morphine in rats

Preoperative analgesics are being increasingly used to provide analgesia in the intraoperative and postoperative period. Opioids reduce anaesthetic requirements, although the effect varies with the different drug and species. The aim of this work was to determine whether buprenorphine reduces the minimum alveolar concentration (MAC) of isoflurane in a dose-related fashion, and whether this effect is similar to morphine when clinical doses of both drugs are used in the rat. Thirty-six male Wistar rats were anaesthetized with isoflurane, and MAC was determined before and after the administration of either buprenorphine or morphine. MAC of isoflurane was determined from alveolar gas samples when a standard noxious stimulus, in the form of a tail clamp, was applied. The duration and degree of reduction of the MAC of isoflurane were recorded. Basic cardiovascular and respiratory measurements were also recorded. Buprenorphine (10, 30 and 100 microg/kg) and morphine (1, 3 and 10 mg/kg) reduced in a dose-dependent fashion the MAC of isoflurane by 15%, 30% and 50%, respectively. Buprenorphine resulted in less cardiovascular and respiratory depression and had a longer-lasting action than morphine. In conclusion, buprenorphine has a dose-related isoflurane sparing effect in the rat similar to that caused by morphine at clinical doses of both drugs.     

Oral administration of diphenyl diselenide protects against cadmium-induced liver damage in rats

Cadmium is an environmental toxic metal implicated in human diseases. In the present study, the effect of diphenyl diselenide, (PhSe)(2), on sub-chronic exposure with cadmium chloride (CdCl(2)) was investigated in rats. Male adult Swiss albino rats received CdCl(2) (10 micromol/kg, orally) and (PhSe)(2) (5 micromol/kg, orally) for a period of 30 days. A number of parameters were examined as indicators of toxicity, including hepatic and renal damage, glucose and glycogen levels and markers of oxidative stress. Cadmium content, liver histology, delta-aminolevulinate dehydratase (delta-ALA-D) activity, metallothionein (MT) levels were also evaluated. Cadmium content determined in the tissue of rats exposed to CdCl(2) provides evidence that the liver is the major cadmium target where (PhSe)(2) acts. The concentration of cadmium in liver was about three fold higher than that in kidney, and (PhSe)(2) reduced about six fold the levels of this metal in liver of rats exposed. Rats exposed to CdCl(2) showed histological alterations abolished by (PhSe)(2) administration. (PhSe)(2) administration ameliorated plasma malondialdehyde (MDA) levels, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and gamma-glutamyl transferase (GGT) activities increased by CdCl(2) exposure. Urea and bilirubin levels increased by CdCl(2) exposure were also reduced by (PhSe)(2). In conclusion, this study demonstrated that co-treatment with (PhSe)(2) ameliorated hepatotoxicity and cellular damage in rat liver after sub-chronic exposure with CdCl(2). The proposed mechanisms by which (PhSe)(2) acts in this experimental protocol are its antioxidant properties and its capacity to form a complex with cadmium.     

重型肝炎患者肝移植术后真菌感染临床分析

目的分析重型肝炎肝移植受体术后真菌感染情况,进一步探讨其易感因素和防治措施。方法回顾性分析我院器官移植中心2003年3月至2006年2月间89例重型肝炎肝移植患者的临床资料并进行讨论。结果89例重型肝炎肝移植患者中21例出现术后真菌感染,感染率为23.6%,较其他病种肝移植更高,其中12例为白念珠菌(57.1%),6例为光滑念珠菌(28.6%),1例为近平滑念珠菌,1例为克柔念珠菌,1例为热带念珠菌。真菌感染多发生在术后1周内,感染部位以呼吸系统为主。结论重型肝炎肝移植患者术后真菌感染以念珠菌属的早期呼吸道感染为主。术前肝性脑病与术后发生真菌感染之间存在相关关系。而一般的白念珠菌感染不会显著地影响重型肝炎肝移植患者的预后。预防性使用抗真菌药物在重型肝炎肝移植术后真菌感染的治疗中具有重要意义。     

Dynamic behavior of hepatitis C virus quasispecies in patients undergoing orthotopic liver transplantation.

We have studied the distribution of viral sequences from the 5' noncoding region and from a fragment of the E2/NS2 region of the hepatitis C virus (HCV) genome in samples obtained before and after liver transplantation in two patients with HCV cirrhosis. The population of viral sequences in both regions were established by sequencing cloned PCR products. In both cases, the complexity of the viral quasispecies decreased after transplantation, although the consensus nucleotide and amino acid sequences remained unchanged. It is suggested that both positive and negative selection and random sampling events contribute substantially in shaping the genetic composition of HCV quasispecies and that recurrence of HCV infection may occur under equilibrium conditions.     

A proteomic analysis of allograft rejection in rats after liver transplantation

In order to understand the allograft rejection in orthotopic liver transplantation (OLT), an allograft re- jection rat model was established and studied by proteomic approach. The protein expression profiles of liver tissues were acquired by fluorescence two-dimensional difference gel electrophoresis (2D DIGE) that incorporated a pooled internal standard and reverse fluorescent labeling method. The expression levels of 27 protein spots showed significant changes in acute rejection rats. Among these spots, 19 were identified with peptide mass fingerprinting using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) after tryptic in-gel digestion. The results of the present paper could be helpful for our better understanding of allograft rejection in organ transplantation.     

A proteomic analysis of allograft rejection in rats after liver transplantation

In order to understand the allograft rejection in orthotopic liver transplantation (OLT), an allograft rejection rat model was established and studied by proteomic approach. The protein expression profiles of liver tissues were acquired by fluorescence two-dimensional difference gel electrophoresis (2D DIGE) that incorporated a pooled internal standard and reverse fluorescent labeling method. The expression levels of 27 protein spots showed significant changes in acute rejection rats. Among these spots, 19 were identified with peptide mass fingerprinting using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) after tryptic in-gel digestion. The results of the present paper could be helpful for our better understanding of allograft rejection in organ transplantation.     

A proteomic analysis of allograft rejection in rats after liver transplantation

In order to understand the allograft rejection in orthotopic liver transplantation (OLT), an allograft rejection rat model was established and studied by proteomic approach. The protein expression profiles of liver tissues were acquired by fluorescence two-dimensional difference gel electrophoresis (2D DIGE) that incorporated a pooled internal standard and reverse fluorescent labeling method. The expression levels of 27 protein spots showed significant changes in acute rejection rats. Among these spots, 19 were identified with peptide mass fingerprinting using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) after tryptic in-gel digestion. The results of the present paper could be helpful for our better understanding of allograft rejection in organ transplantation. These authors contributed equally to this work Supported by the Key Basic Research and Development Program of China (Grant No. 2003CB515506), and in part by the Chinese Human Liver Proteome Project (CNHLPP) (Grant No. 2004BA711A18)     

Circulating sterols as predictors of early allograft dysfunction and clinical outcome in patients undergoing liver transplantation

Introduction

Sensitive and specific assessment of the hepatic graft metabolism after liver transplantation (LTX) is essential for early detection of postoperative dysfunction implying the need for consecutive therapeutic interventions.

Objectives

Here, we assessed circulating liver metabolites of the cholesterol pathway, amino acids and acylcarnitines and evaluated their predictive value on early allograft dysfunction (EAD) and clinical outcome in the context of LTX.

Methods

The metabolites were quantified in the plasma of 40 liver graft recipients one day pre- and 10 days post-LTX by liquid chromatography/tandem mass spectrometry (LC–MS/MS). Plant sterols as well as cholesterol and its precursors were determined in the free and esterified form; lanosterol in the free form only. Metabolites and esterification ratios were compared to the model for early allograft function scoring (MEAF) which is calculated at day 3 post-LTX from routine parameters defining EAD.

Results

The hepatic esterification ratio of all sterols, but not amino acids and acylcarnitine concentrations, showed substantial metabolic disturbances post-LTX and correlated to the MEAF. In ROC analysis, the low esterification ratio of β-sitosterol and stigmasterol from day 1 and of the other sterols from day 3 were predictive for a high MEAF, i.e. EAD. Additionally, the ratio of esterified β-sitosterol and free lanosterol were predictive for all days and the esterification ratio of the other sterols at day 3 or 4 post-LTX for 3-month mortality.

Conclusion

Low ratios of circulating esterified sterols are associated with a high risk of EAD and impaired clinical outcome in the early postoperative phase following LTX.

     

Effects of carvacrol upon the liver of rats undergoing partial hepatectomy

The present study aims to investigate the possible effects of carvacrol obtained from origanum oil upon the regenerative feature of the liver subsequent to partial hepatectomy in rats.Male Wistar Albino rats, weighing 230±30 g, were divided into three experiment groups. Group I (n=8) were used as sham operation group. Group II (n=8) were applied saline solution and hepatectomy. Carvacrol and hepatectomy (73 mg/kg) were applied to Group III (n=8). One dose of test material was injected 1 h before 68% partial hepatectomy. At the end of the experiments, blood and organs were removed. The liver regeneration rate of the rats was calculated measuring the weights of their liver before and after the hepatectomy. Hematoxylin and eosin, interleukin-6 (IL-6) and proliferating cell nuclear antigen (PCNA) treatments were applied to liver sections. Aspartate transaminase (AST), alanine transaminase (ALT), tumor necrosis factor-alpha (TNF-α) and IL-6 levels were determined in serum samples.The liver regeneration, mitotic index and PCNA index increased significantly in rats of Group III over the Group II at the 72nd hour after partial hepatectomy. Histological evaluations were also similar with these results of PCNA and mitotic indexes. In AST, ALT, TNF-α and IL-6 levels, there was no statistically significant difference.According to these results, it is concluded that carvacrol increases the liver regeneration rate.     

Naloxone hyperalgesia and stress-induced analgesia in rats

Since past studies concerning the effects of naloxone on nociception have yielded inconclusive findings, the variables of pain test, baseline sensitivity, and stress condition were examined. Within a pure-bred strain of rats, consistent individual differences did not occur. All three measures of pain responsiveness demonstrated hyperalgesic effects of naloxone, but they differed in their capacity to reflect the effects of analgesia produced by continuous or intermittent electrical shock. By some measures, naloxone reversed the stress-induced analgesia due to intermittent shock; it did not influence the analgesia produced by continuous stress. The data support a model of pain inhibition involving both opioid and non-opioid systems and suggest that the hyperalgesic effects of naloxone can sometime gives rise to erroneous conclusions concerning apparent naloxone-reversability of putative analgesic procedures.     

Effects of soy protein on alcoholic liver disease in rats undergoing ethanol withdrawal

ObjectiveThis investigation attempted to clarify the effects of soy protein on alcoholic liver disease (ALD) in rats undergoing ethanol withdrawal.MethodsAlcoholic liver disease was induced in rats by administration of a low-carbohydrate ethanol liquid diet for 12 weeks, after which the ethanol was withdrawn and the rats were divided into two experimental groups: a control group (EC group) and a soy protein group (EP group) for 4 weeks.ResultsAfter the 12-week ALD-inducing period, the ethanol group had significantly higher hepatic lipid accumulation, oxidative stress and inflammation. We found that the EP group had significantly lower hepatic lipids, malondialdehyde, tumor necrosis factor-α, interleukin (IL)-1β, IL-6, hydroxyproline levels and myeloperoxidase activity compared to the EC group. Moreover, the fecal total cholesterol and total lipids were higher in the EP group. Expression of the hepatic cytochrome P450 2E1 (CYP2E1) protein in the EP group was significantly lower than that in the EC group, and the hepatic peroxisome proliferator-activated receptor (PPAR) α and cytochrome P450 4A (CYP4A) protein expressions in the EP group were significantly higher than those in the EC group. In the histopathological analysis, we also found that soy protein ameliorated fat accumulation in the liver.ConclusionThese results suggest that soy protein may improve alcohol-induced lipid accumulation, oxidative stress and inflammation by decreasing proinflammatory cytokines and CYP2E1 protein expression and by increasing PPARα and CYP4A protein expressions and fecal lipid excretion, thereby producing beneficial effects on ALD during ethanol withdrawal.     

Use of oral buprenorphine ('buprenorphine jello') for postoperative analgesia in rats--a clinical trial

Buprenorphine (0.1, 0.2, 0.3 or 0.4 mg/kg) in a flavoured gelatin base was administered preoperatively to rats undergoing a flank laparotomy. A control group of animals underwent surgery and received only flavoured gelatin. Body weight loss was significantly greater in the group which received no analgesia than in any of the analgesic-treated groups (P < 0.01). Food consumption was reduced significantly in all groups except in those animals which received 0.3 mg/kg buprenorphine. Water consumption was significantly reduced in the control (no analgesia) group (P < 0.001), but was not significantly depressed in the analgesic-treated groups (P > 0.05). Between-group comparisons did not show any significant difference between the different dose rates of analgesia used on either the change in body weight or the reduction in food or water consumption. The results of this study support the use of buprenorphine jelly for post-surgical analgesia in rats. This route of delivery is easy to use, and causes a minimum of stress to the rats.     

Lappaconitine and N-deacetyllappaconitine potentiate footshock-induced analgesia in rats

The effects of lappaconitine (LA) and N-deacetyllappaconitine (DLA) on footshock-induced analgesia (FSIA) were studied by the rat tail flick test. Rats subjected to 90 s nonescaping footshock had a significant increase in tail flick latency. Naloxone (4 micrograms, i.c.v.) partially antagonized the FSIA. After 5 consecutive exposures to footshock, rats developed a complete tolerance to the FSIA. The rats tolerant to FSIA showed a cross-tolerance to morphine- but not LA- and DLA-induced analgesia. Administrations of subanalgesic doses of LA and DLA potentiated the FSIA in both intact and adrenalectomized rats.     

Adverse effects on growth rates in rats caused by buprenorphine administration

As a routine postoperative treatment, a single dose of buprenorphine was given to rats at a dose of 0.05 mg/kg subcutaneously. However, some rats developed abnormal secretions around the nose and mouth and some animals died 3-5 days after surgery and analgesic treatment. At autopsy a yellow fibrous mass was found in the stomach and intestines. Observations of animals given buprenorphine revealed an abnormal ingestion of bedding material. This caused a disturbance to normal digestion, with gastric distension, weight loss or decreased growth rate, constipation and occasionally death. In this study rats were monitored for 6 days following surgery and analgesic treatment. A comparison of growth rates was made between rats given saline and buprenorphine or nalbuphine and between animals kept on bedding or grid floors for the first 24h after treatment. Of the animals held on bedding, the buprenorphine-treated animals did not lose weight as the other animals did, but had on the other hand a decreased growth rate during the measuring period of 6 days after surgery. When denied access to bedding for the first 24 h after surgery, rats given saline or nalbuphine had a reduced weight gain over the first 24 h, similar to the groups held on bedding. Rats held on grid floors and given buprenorphine continued to gain weight for the first 24 h. From day 3, there was no significant difference between the groups, which all gained weight.