Metformin exposure, maternal PCOS status and fetal venous liver circulation: A randomized, placebo-controlled study.

BACKGROUND: Metformin is prescribed to women with polycystic ovary syndrome (PCOS) to prevent pregnancy complications. Children exposed to metformin vs. placebo in utero, have increased head circumference at birth and are more overweight and obese at 8 years of age. Also, maternal PCOS-status seems to alter the long-term cardio-metabolic health of offspring. We hypothesized that the long-term effects of metformin-exposure and/or maternal PCOS may be mediated by circulatory adaptations during fetal life. MATERIAL AND METHODS: This is a sub-study of a larger double-blinded, placebo-controlled trial, where women with PCOS were randomized to metformin (2g/day) or placebo in pregnancy, a total of 487 women. A sub-group of participants (N = 58) took part in this sub-study and had an extended ultrasound examination at gestational week 32, including blood flow velocity and diameter measurements of the umbilical vein (UV), the ductus venosus (DV) and the portal vein (PV). Blood flow volume was calculated and adjusted for estimated fetal weight (EFW) (normalized flow). Metformin exposed fetuses were compared to placebo exposed fetuses. Fetuses of mothers with PCOS (metformin [n = 30] and placebo [n = 28]) were compared to a low-risk reference population (N = 160) by z-score statistics. RESULTS: There was no difference in fetal liver flow between metformin vs. placebo-exposed fetuses. Fetuses of mothers with PCOS had higher EFW (0.63 [95% CI 0.44-0.83] p<0.001), lower normalized UV, DV, PV, and lower total venous liver blood flows than the reference population. CONCLUSION: Metformin during pregnancy did not affect fetal liver blood-flow. In our population, maternal PCOS-status was associated with reduced total venous liver blood-flow, which may explain altered growth and metabolism later in life.

Stimulation of the hepatic arterial buffer response using exogenous adenosine: hepatic rest/stress perfusion imaging.

OBJECTIVES: The hepatic arterial buffer response is a mechanism mediated by adenosine whereby hepatic arterial perfusion (HAP) increases when portal flow decreases, and is implicated in liver disease. The first study aim was to measure HAP in patients undergoing myocardial perfusion imaging (MPI), thus developing hepatic arterial rest/stress perfusion imaging (HAPI). The second aim was to compare adenosine-induced changes in splenic perfusion (SP) and HAP with corresponding changes in myocardial blood flow (MBF). METHODS: Patients had MPI with 82Rb PET/CT using adenosine (n = 45) or regadenoson (n = 33) for stressing. SP and HAP were measured using a first-pass technique that gives HAP rather than total hepatic perfusion. Renal perfusion (RP) was also measured. RESULTS: Mean MBF and HAP increased after both adenosine ([stress-rest]/rest 1.1 and 0.8) and regadenoson (1.4 and 0.6), but the respective changes did not correlate. After adenosine, SP (- 0.48) and RP (- 0.26) both decreased. The change in SP correlated positively with the change in MBF (r = 0.36; p = 0.015) but did not correlate with change in HAP. After regadenoson, SP (0.2) and RP (0.2) both increased. The changes in SP correlated with the changes in MBF (r = 0.39; p = 0.025) and HAP (r = 0.39; p = 0.02). Changes in RP correlated with changes in HAP (r = 0.51; p = 0.0008) but not MBF. Resting SP (r = 0.32; p = 0.004), but not resting HAP, correlated with hepatic fat burden. Adenosine-induced change in HAP also correlated with hepatic fat (r = 0.29; p = 0.05). CONCLUSION: HAPI could be a useful new hepatic function test. Neither splenic 'switch-off' nor hepatic arterial 'switch-on' identifies adequacy of stress in MPI. KEY POINTS: • This article describes a new method for assessing arterial perfusion of the liver and its capacity to respond to an infusion of adenosine, a substance that normally 'drives' hepatic arterial flow. • Hepatic arterial flow increased in response to adenosine, sometimes dramatically. Adenosine is already used clinically to stimulate myocardial blood flow in patients with suspected coronary disease, but the increase in flow did not correlate with the corresponding increase in hepatic arterial flow. • Analogous to the use of adenosine in the myocardium, the increase in hepatic arterial flow in response to adenosine has the potential to be a new clinically useful method for the evaluation of hepatic arterial haemodynamics in liver disease.

Beneficial Effects of the Peroxisome Proliferator-Activated Receptor α/γ Agonist Aleglitazar on Progressive Hepatic and Splanchnic Abnormalities in Cirrhotic Rats with Portal Hypertension.

Recent studies have reported that peroxisome proliferator-activated receptor α (PPARα) agonist decreases intrahepatic resistance, whereas PPARγ agonist reduces portosystemic shunts (PSSs) and splanchnic angiogenesis in cirrhotic rats. The present study investigated the effects of a 21-day treatment with the dual PPARα/γ agonist aleglitazar (Ale) on progressive abnormalities in bile-duct-ligated and thioacetamide-induced cirrhotic rats with portal hypertension (PH). In vivo and in vitro effects were evaluated. Chronic Ale treatment significantly up-regulated PPARα/PPARγ receptors and down-regulated tumor necrosis factor-α (TNF-α) and NF-κB expression in the liver, splanchnic tissues, collateral vessels, and intestines of cirrhotic rats with PH. Notably, Ale improved PH by the suppression of systemic/tissue inflammation, hepatic fibrosis, hepatic Rho-kinase-mediated endothelin-1 hyperresponsiveness, intrahepatic/mesenteric angiogenesis, vascular endothelial growth factor expression, PSS, intestinal mucosal injury, and hyperpermeability in cirrhotic rats. Acute Ale treatment inhibited TNF-α-enhanced endothelin-1-induced contraction of primary hepatic stellate cells, vascular endothelial growth factor-induced migration/angiogenesis of liver sinusoidal endothelial cells, and TNF-α-induced disruption of Caco-2 cell monolayer-epithelial barrier. The present study suggested that Ale can potentially treat relevant abnormalities through the inhibition of inflammatory, vasoconstrictive, angiogenic, and mucosal-disrupted pathogenic markers in cirrhosis. Overall, chronic Ale treatment ameliorated PH syndrome by the suppression of hepatic fibrogenesis, neoangiogenesis, vasoconstrictor hyperresponsiveness, splanchnic vasodilatation, and PSS; and decreased intestinal mucosal injury and hyperpermeability in cirrhotic rats.

Vasopressin and nitroglycerin decrease portal and hepatic venous pressure and hepato-splanchnic blood flow.

BACKGROUND: Various methods are used to reduce venous blood pressure in the hepato-splanchnic circulation, and hence minimise blood loss during liver surgery. Previous studies show that combination of vasopressin and nitroglycerin reduces portal pressure and flow in patients with portal hypertension, and in this study we investigated this combination in patients with normal portal pressure. METHOD: In all, 13 patients were studied. Measurements were made twice to confirm baseline (C1 and BL), during vasopressin infusion 4.8 U/h (V), and during vasopressin infusion combined with nitroglycerin infusion (V + N). Portal venous pressure (PVP), hepatic venous pressure (HVP), central haemodynamics and arterial and venous blood gases were obtained at each measuring point, and portal (splanchnic) and hepato-splanchnic blood flow changes were calculated. RESULTS: Vasopressin alone did not affect PVP, whereas HVP increased slightly. In combination with nitroglycerin, PVP decreased from 10.1 ± 1.6 to 8.9 ± 1.3 mmHg (P < 0.0001), and HVP decreased from 7.9 ± 1.9 to 6.2 ± 1.3 mmHg (P = 0.001). Vasopressin reduced portal blood flow by 47 ± 19% and hepatic venous flow by 11 ± 18%, respectively. Addition of nitroglycerin further reduced portal- and hepatic flow by 55 ± 13% and 30 ± 13%, respectively. Vasopressin alone had minor effects on central haemodynamics, whereas addition of nitroglycerin reduced cardiac index (3.2 ± 0.7 to 2.7 ± 0.5; P < 0.0001). The arterial-portal vein lactate gradient was unaffected. CONCLUSION: The combination of vasopressin and nitroglycerin decreases portal pressure and hepato-splanchnic blood flow, and could be a potential treatment to reduce bleeding in liver resection surgery.

MicroRNA-21-Regulated Activation of the Akt Pathway Participates in the Protective Effects of H2S against Liver Ischemia-Reperfusion Injury.

Maintaining a certain level of hydrogen sulfide (H2S) in ischemia-reperfusion (I/R) is essential for limiting injury to the liver. Exogenous H2S exerts protective effects against this injury, but the mechanisms remain unclear. Liver injury was induced in Wistar rats undergoing hepatic I/R for 30 min, followed by a 3-h reperfusion. Administration of GYY4137 (a slow-releasing H2S donor) significantly attenuated the severity of liver injury and was reflected by reduced inflammatory cytokine production and cell apoptosis, the levels of which were elevated by I/R, while DL-propargylglycine (PAG, an inhibitor of cystathionine γ-lyase [CSE]) aggravated liver injury. Delivery of GYY4137 significantly elevated the plasma levels of H2S and upregulated the expression of microRNA-21 (miR-21), leading to the activation of the Akt pathway, in rat livers subjected to I/R. To further investigate the protective mechanisms of H2S during liver I/R injury, we established a cell model of hypoxia/reoxygenation (H/R) by incubating Buffalo rat liver (BRL) cells under hypoxia for 4 h followed by normoxia for 10 h. The regulatory effect of miR-21 on the Akt pathway by downregulating phosphatase and tensin homolog (PTEN) was validated by luciferase assays. Incubation of sodium hydrosulfide (NaHS), an H2S donor, increased the expression of miR-21, attenuated the reduced cell viability and the increased apoptosis by H/R, in BRL cells. Anti-miR-21 abolished the protective effects of NaHS by inactivating the Akt pathway. In conclusion, the present results indicate the activation of the Akt pathway regulated by miR-21 participates in the protective effects of H2S against I/R-induced liver injury.

Changes of liver hemodynamic and elastography parameters in patients with colorectal liver metastases receiving preoperative chemotherapy: "a note of caution".

BACKGROUND: New systemic chemotherapy agents have improved prognosis in patients with colorectal liver metastases (CLM), but some of them damage the liver parenchyma and ultimately increase postoperative morbidity and mortality after liver resection. The aims of our study were to determine the degree of hemodynamic and pathological liver injury in CLM patients receiving preoperative chemotherapy and to identify an association between these injuries and postoperative complications after liver resection. METHODS: This is a prospective descriptive study of patients with CLM receiving preoperative chemotherapy before curative liver resection from November 2013 to June 2014. All patients had preoperative elastography and hepatic hemodynamic evaluation. We analyzed clinical preoperative data and postoperative outcomes after grouping the patients by chemotherapy type, development of sinusoidal obstructive syndrome (SOS), and development of major complications. RESULTS: Eleven from the 20 patients included in the study received preoperative oxaliplatin-based chemotherapy (OBC). Nine patients had SOS at pathological analysis and five patients developed major complications. Patients receiving preoperative OBC had higher values of hepatic venous pressure gradient (HVPG) and developed more SOS and major complications. Patients developing SOS had higher values of HVPG and developed more major complications. Patients with major complications had higher values of HVPG, and patients with a HVPG of 5 mmHg or greater had more major complications than those under 5 mmHg (20 vs 80%, p = 0.005). CONCLUSIONS: OBC and SOS impair liver hemodynamics in CLM patients. An increase in major complications after liver resection in these patients develops at subclinical HVPG levels.

In vivo inhibitory activity of andrographolide derivative ADN-9 against liver cancer and its mechanisms involved in inhibition of tumor angiogenesis.

It is well known that liver cancer is a highly aggressive malignancy with poor prognosis. Andrographolide (AD), a major bioactive component of Andrographis paniculata (Burm. F.), is a potential anti-cancer pharmacophore and the synthesis of AD derivatives with better cytotoxicity to cancer cells has attracted considerable attentions. In the present study, we evaluated the in vivo inhibitory effects of ADN-9, a 15-benzylidene substituted derivative of AD, on the growth and metastasis of murine hepatoma H22 using an orthotopic xenograft model and a subcutaneous xenograft model, and we further studied the anti-angiogenic action and the related mechanisms of ADN-9 in vivo and in vitro. Importantly, ADN-9 remarkably suppressed the growth and metastasis of both orthotopic and subcutaneous xenograft tumors, and the serum AFP level in orthotopic hepatoma-bearing mice treated with 100mg/kg ADN-9 (ig.) was decreased to the normal level. We also found that ADN-9 showed stronger abilities than AD in shrinking tumors, suppressing the invasion and metastasis of H22 cells, decreasing the MVD and promoting tumor cell apoptosis in subcutaneous xenograft of mice. Additionally, ADN-9 exhibited stronger inhibitory activity than AD against the migration and VEGF-induced capillary-like tube formation in HUVECs, which was further proved to be associated with attenuating VEGF/VEGFR2/AKT signaling pathway. The present research provides the first evidence that a 15-substituted AD derivative is more promising than the parent compound in therapeutic treatment of liver cancer.

The impact of microbubble-enhanced therapeutic ultrasound combined with prothrombin on microwave ablation in the rabbit liver.

AIM: This study aimed to investigate the effect of microbubble-enhanced ultrasound (MEUS) combined with prothrombin on regional hepatic circulation and microwave ablation (MWA) in rabbit livers. MATERIALS AND METHODS: High-pressureamplitude therapeutic ultrasound (TUS) was used to treat 52 surgically exposed livers of healthy New Zealand rabbits: 13 livers were treated with MEUS alone, 13 with MEUS and prothrombin (PMEUS), 13 with ultrasound plus normal saline and 13 with ultrasound plus prothrombin as controls. Contrast-enhanced ultrasound (CEUS) imaging was performed on the exposed livers before and after treatment, and acoustic quantification was done to assess liver perfusion. Then, the liver was divided into two parts, one was used for pathologic examination and the other was ablated with microwave (MWA) and then processedfor pathologic examination. RESULTS: The CEUS images and Peak value after treatment in the PMEUS group were significantly reduced as compared to the remaining 3 groups (p<0.05). Occasional piecemeal hemorrhage was evidenced in the pathological examination in the MEUS group. Obvious cellular degeneration and necrosis with thrombosis were observed in the PMEUS group. Electron microscopy showed endothelial damage in both the MEUS group and PMEUS group. After MWA, coagulated volumes (V) in the PMEUS group were larger than in the remaining 3 groups (p<0.05). The cell ultrastructure disorder wasmore severe in the PMEUS group than in remaining 3 groups. CONCLUSION: PMEUS promotes endothelial injury and produces more obvious thrombotic occlusion, improving the therapeutic effect of MWA on the rabbit liver.

Angiogenesis and portal-systemic collaterals in portal hypertension.

In patients with advanced liver disease with portal hypertension, portal-systemic collaterals contribute to circulatory disturbance, gastrointestinal hemorrhage, hepatic encephalopathy, ascites, hepatopulmonary syndrome and portopulmonary hypertension. Angiogenesis has a pivotal role in the formation of portal-systemic shunts. Recent research has defined many of the mediators and mechanisms involved in this angiogenic process, linking the central roles of hepatic stellate cells and endothelial cells. Studies of animal models have demonstrated the potential therapeutic impact of drugs to inhibit angiogenesis in cirrhosis. For example, inhibition of VEGF reduces portal pressure, hyperdynamic splanchnic circulation, portosystemic collateralization and liver fibrosis. An improved understanding of the role of other angiogenic factors provides hope for a novel targeted therapy for portal hypertension with a tolerable adverse effect profile.

Adenosine Increases Hepatic Artery Flow in Liver Transplant Recipients: A Pilot Study.

BACKGROUND: The aim of this study was to assess the effect of low-dose adenosine on hepatic artery flow (HAF) when administered intraoperatively by continuous infusion. MATERIALS AND METHODS: Between January 2009 and August 2009, 74 patients underwent orthotopic liver transplantation (OLT). Ten patients were enrolled for adenosine treatment, and 64 non-study patients served as controls. After arterial reperfusion, a 16-G central venous catheter was placed in the gastroduodenal artery, and adenosine was continuously infused at doses ranging from 0.7 to 2.8 µg/kg/min for 30 min. HAF and portal vein flow were measured using a transit time flow meter before adenosine infusion, during infusion, and 10 min after infusion. Liver function tests were monitored routinely, duplex ultrasonography was performed on postoperative day 1, and the hepatic artery resistive index measured. The patients were followed for 1 year. RESULTS: Adenosine significantly increased HAF at doses from 0.7 to 2.8 µg/kg/min. The smallest increase in HAF was 24% above the baseline; in 80% of patients, the increase in HAF was >50% of the baseline values. In 2 patients, HAF was increased by >300%. The dosing started at 0.7 µg/kg/min, and 6 of 10 patients responded. Three patients required an increase to 1.4 µg/kg/min. Doses >2.8 µg/kg/min did not further increase HAF. One patient showed a minimal response regardless of the dose. There were no differences between the adenosine group and control group with respect to liver function (aspartate aminotransferase, alanine aminotransferase, total bilirubin, and International Normalized Ratio), platelet count on POD2, hepatic artery resistive index, and post-transplant length of stay, intensive care days, or 1-year patient survival rates. CONCLUSIONS: This pilot study established that adenosine administered directly into the hepatic artery produces a similar effect on HAF in cadaveric liver transplant recipients to that found in the laboratory without producing systemic side effects.

Vasopressin-induced changes in splanchnic blood flow and hepatic and portal venous pressures in liver resection.

BACKGROUND: To minimize blood loss during hepatic surgery, various methods are used to reduce pressure and flow within the hepato-splanchnic circulation. In this study, the effect of low- to moderate doses of vasopressin, a potent splanchnic vasoconstrictor, on changes in portal and hepatic venous pressures and splanchnic and hepato-splanchnic blood flows were assessed in elective liver resection surgery. METHODS: Twelve patients were studied. Cardiac output (CO), stroke volume (SV), mean arterial (MAP), central venous (CVP), portal venous (PVP) and hepatic venous pressures (HVP) were measured, intraoperatively, at baseline and during vasopressin infusion at two infusion rates (2.4 and 4.8 U/h). From arterial and venous blood gases, the portal (splanchnic) and hepato-splanchnic blood flow changes were calculated, using Fick's equation. RESULTS: CO, SV, MAP and CVP increased slightly, but significantly, while systemic vascular resistance and heart rate remained unchanged at the highest infusion rate of vasopressin. PVP was not affected by vasopressin, while HVP increased slightly. Vasopressin infusion at 2.4 and 4.8 U/h reduced portal blood flow (-26% and -37%, respectively) and to a lesser extent hepato-splanchnic blood flow (-9% and -14%, respectively). The arterial-portal vein lactate gradient was not significantly affected by vasopressin. Postoperative serum creatinine was not affected by vasopressin. CONCLUSION: Short-term low to moderate infusion rates of vasopressin induced a splanchnic vasoconstriction without metabolic signs of splanchnic hypoperfusion or subsequent renal impairment. Vasopressin caused a centralization of blood volume and increased cardiac output. Vasopressin does not lower portal or hepatic venous pressures in this clinical setting.

Epidural Blockade Affects the Pharmacokinetics of Propofol in Surgical Patients.

BACKGROUND: Neuraxial blockade reduces the dose requirements of sedative agents. It is unclear whether neuraxial blockade affects the pharmacokinetics and/or the pharmacodynamics of IV hypnotics. We therefore studied the influence of epidural blockade on the pharmacokinetics of propofol in patients scheduled for general surgery. METHODS: Twenty-eight patients were randomly divided into 4 groups, in a double-blind manner, to receive 0, 50, 100, or 150 mg epidural ropivacaine. When the epidural blockade had stabilized, a target-controlled infusion of propofol was started at a target concentration of 1, 2.5, 4, and 6 µg/mL at 0, 6, 12, and 18 minutes, respectively. The infusion was terminated at 24 minutes. Arterial blood samples for blood propofol concentration determination were taken during and up to 150-minute postinfusion. The influence of epidural blockade on propofol pharmacokinetics was determined by mixed-effects modeling. RESULTS: With a ropivacaine dose increasing from 0 to 150 mg, the number of blocked segments (median [range]) increased from 0 (0-3) to 16 (6-21). With increasing epidural dose, blood propofol concentration increasingly exceeded target concentration. An epidural blockade of 20 segments reduced propofol's elimination clearance from 2.64 ± 0.12 to 1.87 ± 0.08 L/min. Adjusting for weight and sex further improved the propofol pharmacokinetic model. CONCLUSIONS: Epidural blockade affects the pharmacokinetics of propofol and the performance of a target-controlled infusion of propofol. At an epidural ropivacaine dose that blocks 20 segments, the propofol dosage or target concentration may be reduced by 30% compared with when no epidural blockade is present. An epidural-induced reduction in hepatic and/or renal blood flow may explain this pharmacokinetic interaction.

Adrenal steroidogenesis disruption caused by HDL/cholesterol suppression in diethylstilbestrol-treated adult male rat.

The synthetic estrogen diethylstilbestrol is used to prevent miscarriages and as a therapeutic treatment for prostate cancer, but it has been reported to have adverse effects on endocrine homeostasis. However, the toxicity mechanism is poorly understood. Recently, we reported that diethylstilbestrol impairs adrenal steroidogenesis via cholesterol insufficiency in adult male rats. In the present study, we found that the adrenal cholesterol level was significantly reduced without of the decrease in other precursors in the adrenal steroidogenesis 24 h after a single dose of diethylstilbestrol (0.33 µg/g body mass). The serum HDL/cholesterol level was also reduced only 12 h after the diethylstilbestrol exposure. The level of Apo E, which is indispensable for HDL/cholesterol maturation, was decreased in both the HDL and VLDL/LDL fractions, whereas the level of Apo A1, which is an essential constituent of HDL, was not altered in the HDL fraction. Because the liver is a major source of Apo E and Apo A1, the secretion rates of these proteins were examined using a liver perfusion experiment. The secretion rate of Apo A1 from the liver was consistent between DES-treated and control rats, but that of Apo E was comparatively suppressed in the DES-treated rats. The disruption of adrenal steroidogenesis by diethylstilbestrol was caused by a decrease in serum HDL/cholesterol, which is the main source of adrenal steroidogenesis, due to the inhibition of Apo E secretion from the liver.

Hepatoblastoma in Children With Congenital Portosystemic Shunts.

Two children developed hepatoblastoma concurrent with congenital portosystemic shunts (PSSs) (Abernethy malformations). Both underwent operative ligation of their PSSs. One received concurrent tumor resection, whereas the other was deemed initially unresectable and underwent biopsy followed by neoadjuvant chemotherapy. Although benign hepatic masses, such as focal nodular hyperplasia and nodular regenerative hyperplasia, are common in patients with Abernethy malformations, malignant tumors have also been documented and should always be considered in the differential diagnosis of a patient with a congenital PSS and a hepatic mass.

Preclinical Assessment of the Efficacy of Anti-Angiogenic Therapies in Hepatocellular Carcinoma.

Diffuse hepatocellular carcinoma (HCC) is a complex affliction in which comorbidities can bias global outcome of cancer therapy. Better methods are thus warranted to directly assess effects of therapy on tumor angiogenesis and growth. As tumor angiogenesis is invariably associated with changes in local blood flow, we assessed the utility of ultrasound imaging in evaluation of the efficacy of anti-angiogenic therapy in a spontaneous transgenic mouse model of HCC. Blood flow velocities were measured monthly in the celiac trunk before and after administration of sorafenib or bevacizumab at doses corresponding to those currently used in clinical practice. Concordant with clinical experience, sorafenib, but not bevacizumab, reduced microvascular density and suppressed tumor growth relative to controls. Evolution of blood flow velocities correlated with microvascular density and with the evolution of tumor size. Ultrasound imaging thus provides a useful non-invasive tool for preclinical evaluation of new anti-angiogenic therapies for HCC.

Computed tomography findings of hepatic veno-occlusive disease caused by Sedum aizoon with histopathological correlation

This study investigated the value of computed tomography (CT) in the diagnosis and treatment of hepatic veno-occlusive disease (HVOD) caused by Sedum aizoon (SA). The clinical manifestations, treatment results, imaging findings, and histological findings of the liver were analyzed in 39 patients with HVOD caused by SA. Hepatomegaly, liver dysfunction, abdominal effusion, and geographic density changes on liver CT scans were found in all 39 patients. The pathological findings of histological liver examination included swelling and point-like necrosis of liver cells, significant expansion and congestion of the sinuses, endothelial swelling, and wall thickening with incomplete lumen occlusion of small liver vessels. CT geographic density changes were confirmed by histological examination of the liver in 18 patients. Sixteen patients with small amounts of ascites that started within 4 weeks of treatment recovered completely or significantly improved after symptomatic and supportive treatment. However, only 43.75% of the patients with larger amounts of ascites improved following symptomatic and supportive treatment. In conclusion, liver CT examination is a valuable, safe, and noninvasive tool for the diagnosis of HVOD caused by SA. In selected cases, liver CT examination may replace liver biopsy and histological analysis.

[THE ROLE OF HYDROGEN SULFIDE IN REGULATION OF CIRCULATION BLOOD LIVER].

It was shown in acute experiments on laboratory rats that intraportalinjectionof hydrogen sulfide's precursor L-cysteine (15 mg/kg)caused dilatation of the intrahepatic vessels. As a result, systemic blood pressure (SBP) and blood pressure in the portal vein (PVP) significantly decreased on 17,6 and 24,5%, respectively, and the rate of local blood flow in the liver (LF) and its blood filling (BF) increased on 28,2 and 24,4% respectively. Application of hydrogen sulfide donor NaHS (7 mg/kg) resulted in similarly directed changes: SBP and PVP decreased on 20,8% i 26,2% respectively,LF and BF increased on 16,4% and 30,9% respectively. Application of L-cysteine in the conditions of tsystationin-gamma-lyase blockade by LD-proparhilhlitsyn led to an increase in SBP on 20,4 % and PVP on 26,6% and a decrease of BF on 21,5% and LF in the liver on 11,7% comparing with baseline values of these parameters. So, blockade of tsystationin-gamma-lyase not only completely removed the effects of L-cysteine, but also inhibited synthesis of H2S from its endogenous predecessors,which led to vasoconstriction of liver's blood vessels and, consequently, to an increase of blood pressure and a decrease of liver blood flow rat's and volume of blood deposited in liver.

Computed tomography findings of hepatic veno-occlusive disease caused by Sedum aizoon with histopathological correlation.

This study investigated the value of computed tomography (CT) in the diagnosis and treatment of hepatic veno-occlusive disease (HVOD) caused by Sedum aizoon (SA). The clinical manifestations, treatment results, imaging findings, and histological findings of the liver were analyzed in 39 patients with HVOD caused by SA. Hepatomegaly, liver dysfunction, abdominal effusion, and geographic density changes on liver CT scans were found in all 39 patients. The pathological findings of histological liver examination included swelling and point-like necrosis of liver cells, significant expansion and congestion of the sinuses, endothelial swelling, and wall thickening with incomplete lumen occlusion of small liver vessels. CT geographic density changes were confirmed by histological examination of the liver in 18 patients. Sixteen patients with small amounts of ascites that started within 4 weeks of treatment recovered completely or significantly improved after symptomatic and supportive treatment. However, only 43.75% of the patients with larger amounts of ascites improved following symptomatic and supportive treatment. In conclusion, liver CT examination is a valuable, safe, and noninvasive tool for the diagnosis of HVOD caused by SA. In selected cases, liver CT examination may replace liver biopsy and histological analysis.

Protective Effect of Nitric Oxide on Liver Circulation from Ischemia Reperfusion Injury.

INTRODUCTION: The reduction of endogenous nitric oxide (NO) production during hepatic ischemia-reperfusion injury, generally via a reduction in endothelial NO synthase activity, leads to liver injury. We hypothesized that administration of an exogenous NO donor into the portal vein may ameliorate hepatic blood flow reduction after a period of ischemia. MATERIAL AND METHODS: A total of 90 min of ischemia (portal vein and hepatic artery) was applied in 15 anesthetized pigs, using the Pringle method under sevoflurane anesthesia. All animals were administered either saline (control group, n = 8) or sodium nitroprusside (SNP, n = 7) as exogenous NO donor drugs into the portal vein, 30 min before and after ischemia. The portal venous blood flow and hepatic artery blood flow were measured continuously using transonic flow probes attached to each vessel. Endogenous NO (NOx = NO2- + NO3-) production was measured every 10 min using a microdialysis probe placed in the left lobe of the liver. RESULTS: In the SNP group, portal venous flow remained unchanged and hepatic artery flow significantly increased compared to baseline. Although the production of liver tissue NOx transiently decreased to 60% after ischemia, its level in the SNP group remained higher than the control saline group. CONCLUSION: Regional administration of SNP into the portal vein increases hepatic arterial flow during ischemia reperfusion periods without altering mean systemic arterial pressure. We speculate that administration of an exogenous NO donor may be effective in preventing liver injury via preservation of total hepatic blood flow.