The industrial chemical 1,3-butadiene (BD) is a potent carcinogen in mice and a weak one in rats. This difference is generally related to species-specific burdens by the metabolites 1,2-epoxy-3-butene (EB), 1,2:3,4-diepoxybutane (DEB), and 3,4-epoxy-1,2-butanediol (EBD), which are all formed in the liver. Only limited data exist on BD metabolism in ...

Summary 1. The aim of the study was to investigate the mechanisms involved in the clearance of isosteviol by using the isolated perfused rat liver. 2. Six livers of male Sprague-Dawley rats were perfused with 15.7 mumol isosteviol in a recirculating system. Perfusate and bile samples were collected for 60 ...

We have previously shown that the antinociceptive effect of nitrous oxide (N(2)O) in the rat hot plate test is sensitive to antagonism by antisera against the endogenous opioid peptide beta-endorphin. Moreover, N(2)O-induced antinociception is reduced by inhibition of nitric oxide (NO) production in the brain. To test the hypothesis that ...

BACKGROUND: Discordant xenotransplantation, the grafting of organs from one phylogenic species to another, results in hyper-acute rejection (HAR). HAR is associated with the deposition of recipient preformed xenoreactive natural antibodies and complement on the endothelium of the donor organ, leading to activation and apoptosis of the endothelium, an event associated ...

This work deals with the construction and performance of a device designed to measure the oxygen consumption by the liver during hypothermic perfusion in the rat model. Due to its simple design and the utilization of standard materials, it could serve to determine the role of oxygenation during hypothermic perfusion ...

Ascorbate has both antioxidant and pro-oxidant activities. We have previously shown that plasma levels of ascorbate induce constriction and blockade of dilatation mediated by endothelium-derived hyperpolarizing factor (EDHF). In this study we sought to determine if these detrimental actions were mediated by a prooxidant action of ascorbate. Since trace levels ...

BACKGROUND: [Tc-99m-N(mpo)(PNP5)](+) (Tc-99m-N-MPO: Hmpo = 2-mercaptopyridine N-oxide and PNP5 = N-ethoxyethyl-N,N-bis[2-(bis(3-methoxypropyl)phosphino)ethyl]amine) is a new Tc-99m radiotracer useful for myocardial perfusion imaging. The main objective of this study is to elucidate the mechanism for myocardial localization and fast liver clearance of Tc-99m-N-MPO in comparison with Tc-99m-sestamibi ([Tc-99m-(MIBI)(6)](+): MIBI = 2-methoxy-2-methylpropylisonitrile). METHODS ...

BACKGROUND/OBJECTIVE: Carbon monoxide (CO) produced by haem-oxygenase isoforms (HO-1 & HO-2) is involved in the regulation of systemic vascular tone. We aimed to elucidate the vasoregulatory role of CO in the microcirculation in normal and thioacetamide cirrhotic rat livers. METHODS: Haem-oxygenase expression was examined by Western blot. Total HO enzymatic ...

BACKGROUND: The microcirculation was assessed in the livers of human decay accelerating factors (hDAF) and wild-type transgenic rats by fluorescent intravital microscopy, histology and histomorphology to determine the benefits of hDAF expression for the microcirculation of a rat liver xenograft perfused with human blood. METHODS: Male hDAF transgenic rats (group ...

17beta-estradiol is synthesized de novo in the rat hippocampus. However, the regulatory mechanism of hippocampal estradiol synthesis has remained unclear. We investigated the effects of social isolation on rat hippocampal estradiol synthesis. Rats were divided into two groups: social isolation and pair housed group. Socially isolated rats were housed individually ...

A system is presented demonstrating the high-temporal resolution coupling of low-flow push-pull perfusion sampling (LFPS) to capillary electrophoresis for the absorbance measurement of ascorbate at the rat vitreoretinal interface. This system holds all separation components at a low pressure as the means for withdrawing sample during LFPS. The system uses ...

AIM: Transformation and possible metabolic effects of extracellular NAD+ were investigated in the livers of mice (Mus musculus; Swiss strain) and rats (Rattus novergicus; Holtzman and Wistar strains). METHODS: The livers were perfused in an open system using oxygen-saturated Krebs/Henseleit-bicarbonate buffer (pH 7.4) as the perfusion fluid. The transformation of ...

BACKGROUND: Carbon dioxide (CO2) dose-dependently decreases minimum alveolar concentration (MAC) of anaesthetics in rats. CO2 also dose-dependently decreases cerebrospinal fluid pH. N-methyl-D-aspartate (NMDA) channels exhibit pH sensitivity and are putative targets for inhaled anaesthetics. We hypothesized that CO2 dose-dependently decreases rat NMDA channel current via an acidifying effect at concentrations ...

BACKGROUND AND AIM: The effect of increased sinusoidal pressure on the portal tract in Budd-Chiari syndrome (BCS) is as yet not elucidated. Our aim was to investigate portal changes in a newly-developed rat model for BCS. METHODS: We created an outflow obstruction in Sprague-Dawley rats (n = 6) by diameter ...

The liver plays a central role in intermediate metabolism. Accumulation of liver fat (steatosis) predisposes to various liver diseases. Steatosis and abnormal muscle energy metabolism are found in insulin-resistant and type-2 diabetic states. To examine hepatic energy metabolism, we measured hepatocellular lipid content, using proton MRS, and rates of hepatic ...

Adenovirus-mediated kallikrein delivery has been shown to promote blood vessel growth in the limb under both ischemic and normoperfused conditions. Here we investigated whether a continuous supply of kallikrein and kinin peptide can induce neovascularization in a rat model of hindlimb ischemia. Rats underwent femoral artery ligation and localized injection ...

The role of haptoglobin in liver cell entry of acellular native hemoglobin, and cross-linked human hemoglobin, a potentially useful oxygen-carrier alternative in transfusion medicine, was examined in the recirculating, perfused rat liver preparation. Doses of tritiated native human or beta-chain [trimesoyl-(Lys82)beta-(Lys82)beta] cross-linked human hemoglobin were preincubated with haptoglobin-containing rat plasma ...

AIM: To investigate whether the major kavalactone kavain imposes adverse effects on the liver ultrastructure and function by affecting vascular and microvascular architecture and altering hepatocellular morphology. METHODS: Kavain solution (10 microg/mL or 43.5 micromol/L) was perfused for 2 h in isolated rat livers. After standard fixation and tissue preparation, ...

Real-time myocardial contrast echocardiography (MCE) is a noninvasive perfusion imaging method, whereas technical and resolution problems impair its application in small animals. Hence, we investigated the feasibility of MCE in experimental cardiovascular set-ups involving healthy and infarcted myocardium in rats. Twenty-five male Wistar rats were examined under volatile anesthesia (2.5% ...

PURPOSE: To investigate the value of perfusion-weighted MRI in the evaluation of the intranodular hemodynamic characteristics of dysplastic nodules (DNs) and hepatocellular carcinomas (HCCs) in an experimental rat model. MATERIALS AND METHODS: A total of 40 rats with chemically-induced DNs and HCCs were investigated. Single-slice gadolinium-enhanced perfusion-weighted MRI was performed ...

BACKGROUND: Perihemorrhagic pathophysiology of spontaneous intracerebral hemorrhages (ICH) remains unclear. Recently, ischemic changes in the perihemorrhagic zone (PHZ) have been discussed as a potential source of secondary damage. In this study, we focussed on diffusion and perfusion characteristics of experimental ICH. METHODS: Experimental ICH was induced with a double injection ...

PURPOSE: To investigate the mechanism of the termination of ocular dominance column plasticity by electrophysiologic analysis and 2-dimensional electrophoresis-mass spectrography (2-DE/MS). METHODS: The changes in ocular dominance columns following monocular deprivation were electrophysiologically detected in 22-day-old, 100-day-old and chondroitinase-perfused 100-day-old rats. Total protein of grey matter of the primary visual ...

Current techniques for the preservation of donor livers typically rely on cold temperatures (approximately 0-4 degrees C) to slow down metabolic processes. Recently, normothermic extracorporeal liver perfusion (NELP) has regained interest as a potentially promising approach for long-term liver preservation. Unlike cold-storage techniques, NELP attempts to maintain the liver in ...

BACKGROUND/AIMS: Cyclooxygenase-1 (COX-1) is overexpressed in sinusoidal endothelial cells (SEC) of cirrhotic rat livers, and through an enhanced production of vasoconstrictor prostanoids contributes to increase intrahepatic resistance. Our study was aimed at investigating the role of enhanced AA bioavailability modulating the hepatic vascular tone of cirrhotic livers and identifying which ...

BACKGROUND/AIMS: Liver function appears to be well maintained in old age. However, the current state of knowledge about liver aging processes is incomplete. In this study, using extracorporeal liver perfusion model, we evaluated the differences between liver function in young and old rats. METHODOLOGY: Livers were harvested from groups of ...

Liver grafts are frequently discarded due to steatosis. Steatotic livers can be classified as suboptimal and deteriorate rapidly during hypothermic static preservation, often resulting in graft nonfunction. Hypothermic machine perfusion (MP) has been introduced for preservation of donor livers instead of cold storage (CS), resulting in superior preservation outcomes. The ...

Isolated perfusion of rat livers (IPRL) represents an attractive set-up to be used as a an evaluative tool in the easy and reproducible assessment of liver injury, allowing for screening of new approaches to organ preservation without the expenditure of actual transplantation experiments. Depending on the pathology under investigation, controversy ...

The venom of Bothrops insularis snake, known in Brazil as jararaca ilhoa, contains a variety of proteolytic enzymes such as a thrombin-like substance that is responsible for various pharmacological effects. B. insularis venom chromatography profile showed an elution of seven main fractions. The thrombin-like activity was detected in fractions I ...

PURPOSE: To set up and validate a viable perfused rat pancreas model suitable for pharmacokinetic studies. MATERIALS AND METHODS: We setup and conducted multiple indicator dilution studies in the single pass perfused rat pancreas. The distribution of the reference markers [99mTc]-red blood cells (RBC), [14C]-sucrose, and [3H]-water, and tolbutamide were ...

Nitrite reduction to nitric oxide (NO) may be potentiated by a nitrite reductase activity of deoxyHb and contribute to systemic hypoxic vasodilation. The effect of nitrite on the pulmonary circulation has not been well characterized. We explored the effect of nitrite on hypoxic pulmonary vasoconstriction (HPV) and the role of ...

BACKGROUND: Butyrate is the main nutrient for the colonocytes but the effect of the fraction reaching the liver is not totally known. A decrease in tissue ATP content and increase in respiration was previously demonstrated when livers were perfused with short-chain fatty acids (SCFA) such as butyrate, or octanoate. In ...

OBJECTIVE: Baroreflex sensitivity is reduced in women with preeclampsia. The aim of this study was to determine whether baroreflex control of renal sympathetic nerve activity (RSNA) is altered in pregnant rats with reduced uterine perfusion (a model of human preeclampsia). METHODS: Uterine perfusion was reduced in the third trimester by ...

Mitomycin C (MMC) is an alkylating agent which suppresses allogeneic T-cell responses. We analyzed the effect of graft perfusion with MMC on transplant survival. Hearts from Brown-Norway (BN) rats were perfused ex vivo with MMC-containing solution, stored and implanted into Lewis (LEW) rats. In order to analyze the in vivo ...

The nasal vascular permeability of ovablumin (OVA)-sensitized Brown Norway rats was evaluated by analyzing a brilliant blue concentration in perfusate from the nose after exposure of the nasal mucus to OVA. Oral administration of Lactobacillus GG and L. gasseri TMC0356 significantly inhibited the increase in nasal vascular permeability (P<0.01). The ...

OBJECTIVE: To investigate the effect of Euro-Collins and Belzer solutions in a sequential preservation of the pancreas. METHODS: Forty-five Wistar-EPM rats were divided into four groups, according to the solution used during preservation: (1) saline solution (SF): animals perfused and preserved with saline solution; (2) Euro-Collins group (C): animals perfused ...

BACKGROUND: Curcumin has profound antioxidant and anti-inflammatory properties. This research assessed the effect of curcumin on liver preservation. METHODS: Sprague-Dawley rat livers were flushed with different preservation solutions [Euro-Collins solution (EC), phosphate buffer saline (PBS), University of Wisconsin solution (UW)] with or without curcumin (25-200 microM) and stored at 4 ...

The aim of the present study was to investigate the effects of the alpha2-adrenoceptor antagonist yohimbine on blood pressure and heart rate (HR) regulation, as well as on adrenergic and serotoninergic neurotransmission, in fructose hypertensive (F) rats. The anterior hypothalamic area of control (C) and F rats was perfused with ...

Pregnancy is a very important period in mammals. Various morphological and functional changes can be observed. Some studies examining nasal epithelial structure deal with changes found in pregnancy. In this study, a total of 16 adult female Sprague Dawley rats (8 control and 8 pregnant) were used. They were anesthetized ...

OBJECTIVE: University of Wisconsin (UW) solution continues to be the most commonly used solution for intra-abdominal organs. However, it is expensive. Therefore, we have formulated HuaXi-1 (HX-1) solution. The aim of this research was to assess the effect of HX-1 solution compared to UW, Collins 2, and hypertonic citrate solutions ...

BACKGROUND AND AIMS: Portal hypertension in cirrhosis is mediated in part by increased intrahepatic resistance, reflecting an increased sensitivity of the hepatic microvasculature to vasoconstrictors. Activation of the RhoA/Rho-kinase pathway is essential for contraction of vascular smooth muscle. The aim of this study was to investigate RhoA/Rho-kinase mediated regulation of ...

Homologous or heterologous erythrocytes have been widely used for the estimation of intravascular volume of the liver. However, cross-species blood mediates immune response in the organ, and foreign cells are rapidly cleared from the plasma, indicating that heterologous erythrocytes may not be a suitable marker for determination of vascular space. ...

Assessment of complement 4 (C4) levels in experimental animals is used as a marker for activation of the classical complement pathway. The objective of this study was to develop a method for measuring C4 concentrations in the rat brain. An ELISA (sensitivity = 0.5 ng C4/ml) was used to measure ...

We evaluated the effect of ethynylestradiol (EE) administration (5 mg/kg b.wt. s.c., for 5 consecutive days) on the expression and activity of multidrug resistance-associated protein 3 (Mrp3) in rats. Western blotting analysis revealed decreased Mrp2 (-41%) and increased Mrp3 (+200%) expression by EE. To determine the functional impact of up-regulation ...

BACKGROUND/AIMS: Cirrhotic livers have a deficient vasodilator response to nitric oxide (NO). The vasodilator effect of NO is normally limited by the degradation of its second messenger cyclic guanosine 3', 5' monophosphate by phosphodiesterases. We investigated (1) the phosphodiesterase-5 (PDE-5) expression in normal and cirrhotic rat livers, (2) the location ...

Carboxy PROXYL is a useful extracellular paramagnetic contrast reagent in electron spin resonance (ESR) and magnetic resonance imaging (MRI). Active transfer of the probe was investigated using an in situ liver model in rats. Carboxy PROXYL, a nitroxyl spin probe, was perfused into in situ liver perfusion system from Wistar ...

PURPOSE: To characterize the relationship between applied power and treatment duration in their effect on extent of coagulation produced with a 2.45-GHz microwave applicator in both an ex vivo and a perfused in vivo liver model. MATERIALS AND METHODS: All experimentation was approved by the Institute of Animal Care and ...

We previously showed that naproxen induced the oxidative stress in the liver microsomes and the isolated hepatocytes of rats. In this study, the in situ effect of naproxen on the rat liver tissue was investigated, using the isolated perfused liver from the view-point of the naproxen-induced hepatotoxicity. The leakage of ...

Development, validation and application of an HPLC assay for new antiviral nucleoside analogues AM365 and AM188 in isolated perfused rat liver perfusate and bile were performed. An analytical column (Phenosphere-NEXT, 250 x 4.6 mm, C(18), 4 microm, Phenomenex) was used in tandem with a guard column (4 x 3 mm, ...

The initiating event in preeclampsia is thought be to reduced uteroplacental perfusion. Although we have reported previously that chronic reductions in uterine perfusion pressure (RUPP) in pregnant rats results in hypertension and enhanced endothelin production, the factors linking placental ischemia and endothelial cell activation remain unclear. The purpose of this ...

Although rat is the most widely used model of glucocorticoid programming of the fetus, the role of rat placental 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) in the transplacental pharmacokinetics of the naturally occurring glucocorticoid, corticosterone, has not yet been fully elucidated. In this study, expression of 11beta-HSD2 in the rat placenta ...