NS Control Group Research Articles

The therapeutic function of the chemokine RANTES on the H22 hepatoma ascites model

This study aimed at analyzing the therapeutic function of the chemokine RANTES on the H22 hepatoma ascites model and preliminarily explore the mechanism of RANTES in malignant ascites to provide an important reference for applying chemokines in anti-tumor therapy. The murine H22 hepatoma ascites model was used. Three treatment groups were analyzed: a RANTES treatment group, an IL-2 control group, and an NS control group. Two regimens of early treatment and late treatment were designed, and the therapeutic effect of RANTES on malignant ascites was studied by measuring changes in mouse body weight and abdominal circumference and observing the survival time. The expression of TNF-α, IFN-γ, TGF-β1, and MCP-1 in mouse ascites was detected by ELISA, and the chemotactic function of RANTES on B lymphocytes and T lymphocytes was analyzed by flow cytometry. In the early and late treatment regimens, RANTES could effectively inhibit the increase in mouse body weight and abdominal circumference in the murine H22 hepatoma ascites model. The secretion of TNF-α and IFN-γ, which had anti-tumor effects, was higher in the RANTES treatment group than in the control groups (P < 0.05), whereas the secretion of TGF-β1 and MCP-1, which promoted tumor growth, invasion, and metastasis, was lower than in the control groups (P < 0.05). RANTES had chemotactic effects on CD4(+) and CD8(+) T lymphocytes; therefore, the percentage of CD3, CD4, and CD8 in the mouse ascites in the RANTES treatment group was significantly higher than in the NS control and IL-2 treatment groups, and the CD4/CD8 ratio was also significantly higher. RANTES can effectively inhibit the increase in body weight and abdominal circumference and significantly extend survival time in mice in the H22 hepatoma ascites model.

Calcium montmorillonite clay reduces urinary biomarkers of fumonisin B1 exposure in rats and humans

Fumonisin B1 (FB1) is often a co-contaminant with aflatoxin (AF) in grains and may enhance AF's carcinogenicity by acting as a cancer promoter. Calcium montmorillonite (i.e. NovaSil, NS) is a possible dietary intervention to help decrease chronic aflatoxin exposure where populations are at risk. Previous studies show that an oral dose of NS clay was able to reduce AF exposure in a Ghanaian population. In vitro analyses from our laboratory indicated that FB1 (like aflatoxin) could also be sorbed onto the surfaces of NS. Hence, our objectives were to evaluate the efficacy of NS clay to reduce urinary FB1 in a rodent model and then in a human population highly exposed to AF. In the rodent model, male Fisher rats were randomly assigned to either FB1 control, FB1 + 2% NS or absolute control group. FB1 alone or with clay was given as a single dose by gavage. For the human trial, participants received NS (1.5 or 3 g day−1) or placebo (1.5 g day−1) for 3 months. Urines from weeks 8 and 10 were collected from the study participants for analysis. In rats, NS significantly reduced urinary FB1 biomarker by 20% in 24 h and 50% after 48 h compared to controls. In the humans, 56% of the urine samples analysed (n = 186) had detectable levels of FB1. Median urinary FB1 levels were significantly (p < 0.05) decreased by >90% in the high dose NS group (3 g day−1) compared to the placebo. This work indicates that our study participants in Ghana were exposed to FB1 (in addition to AFs) from the diet. Moreover, earlier studies have shown conclusively that NS reduces the bioavailability of AF and the findings from this study suggest that NS clay also reduces the bioavailability FB1. This is important since AF is a proven dietary risk factor for hepatocellular carcinoma (HCC) in humans and FB1 is suspected to be a dietary risk factor for HCC and oesophageal cancer in humans.

Protective effect of peroxisome proliferator-activated receptor γ agonist 15d-PGJ2 against reperfusion injuryin small-for-size rat liver grafts

Objective To investigate the protective effect of peroxisome proliferator-activated receptor γ (PPARγ) agonist 15d-PGJ2 against reperfusion injury in small-for-size liver grafts and its probable mechanisms. Methods 108 adult male SD rats were randomly divided into three groups: ( 1 ) 15d-PGJ2 group; (2) 15d-PGJ2 + GW9662 group; (3) NS control group. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels at 6, 24 and 72 h after reperfusion and histopathological changes were analyzed, the contents of malondialdehyde (MDA) and superoxide dismutase (SOD) in liver grafts after 24 h were determined, myeloperoxidase (MPO) activity was examined to assay neutrophil infiltration into the grafts at 24 h after reperfusion, and transforming growth factor (TGF)-α levels at 24 h after reperfusion were measured by using enzyme-linked immunosorbent assay ( ELISA method). Results As compared with NS control group and 15d-PGJ2 + GW9662 group, serum AST and ALT levels were significantly reduced at 6, 24 and 72 h after reperfusion in 15d-PGJ2 group (P ＜0. 01 ). Histopathological analysis revealed apparent bulb-like degeneration, hepatic sinusoid dilation, and inflammatory cell infiltration in periportal area at 24 h in NS group and 15d-PGJ2 + GW9662 group after transplantation, while in the 15d-PGJ2 group, minimal damage was observed at 24 h after transplantation under the light microscopy, the contents of MDA were lower and SOD levels were higher than in other groups ( P ＜0. 01 ). As compared with NS group and 15d-PGJ2 + GW9662 group, TNF-α levels and MPO activity at 24 h after transplantation were also significantly decreased in 15d-PGJ2 group (P ＜ 0. 01 ). Conclusion PPARγagonist 15d-PGJ2 could ameliorate reperfusion injury in small-for-size liver grafts significantly, which was mediated in part by increasing antioxidant ability, inhibiting lipid peroxidation, and down-regulating inflammatory reaetion. Key words: PPARγ; Liver transplantation; Repeffusion injury

Administration of hydrogen sulfide intraperitoneally reverses the hyporesponsiveness of rat pulmonary artery induced by lipopolysaccharide and its relationship with carbon monoxide

To explore the effect of hydrogen sulfide (H(2)S) on abnormal pulmonary artery reactivity induced by lipopolysaccharide (LPS) and its relationship with carbon monoxide (CO). Forty eight rats were divided into four groups randomly according to table of random number: control group (normal saline, NS), LPS group, a donor of H(2)S sodium hydrosulfide (NaHS)+LPS group, and NaHS+NS group (n=12 in each group). Rats were given LPS by intratracheal instillation (0.8 ml/kg). 0.5 ml of NaHS (28 μmol/kg) was injected intraperitoneally 10 minutes before LPS or NS instillation and 2 hours after LPS or NS instillation in NaHS+LPS and NaHS+NS groups. Twelve hours after instillation of LPS, 6 rats from each group were sacrificed. The pulmonary artery rings (PARs) were prepared and the changes in cumulative relaxation response of PARs to NaHS were detected before and after incubation with an inhibitor of heme oxygenase-1 (HO-1) zinc protoporphyrinIX (ZnPPIX) using isolated vascular ring tension detecting technique. Twelve hours after LPS instillation, the remaining 6 rats in each group were sacrificed, and the contents of carboxyhemoglobin (COHb) in efferent pulmonary blood (EPB) and afferent pulmonary blood (APB) were measured, and the difference between the contents of COHb in EPB and that of APB was calculated to represent content of CO from pulmonary circulation. In the present study, compared with control group, after the instillation of LPS the percentage of relaxation response of PARs to NaHS was significantly declined [(75.72±7.22)% vs. (96.40±4.40)%, P<0.01]. After being incubated with ZnPPIX, the decreased relaxation response of PARs to NaHS induced by LPS was further depressed [(62.91±8.22)% vs. (75.72±7.22)%, P<0.01]. Administration of NaHS intraperitoneally reversed the hyporesponsiveness of PARs to NaHS, the percentage of relaxation response of PARs to NaHS was significantly increased [(94.65±8.45)% vs. (75.72±7.22)%, P<0.01]. However ZnPPIX also attenuated the effect [(83.75±9.76)% vs. (94.65±8.45)%, P<0.01]. NO significant changes were observed between NaHS+NS group and control group, also between the results before and after ZnPPIX incubation . Compared with control group, the difference between the contents of COHb in EPB and that of APB increased after instillation of LPS [(3.12±0.48)% vs. (2.12±0.32)%, P<0.05], which further increased after intraperitoneal administration of NaHS [(4.03±0.56)%, P<0.01]. The results suggested that intraperitoneal administration of H(2)S could reverse hyporesponsiveness of PARs to H(2)S induced by LPS, and the result might be related to an intensification of HO-1/CO system in pulmonary artery tissue.

Effects of 15-deoxy-△12,14-prostagliandxin J2 on the expression of type I collagen in hypertrophic scar of rabbit ears

Objective To investigate the effect of 15d-PGJ2 on the expression of type Ⅰ collagen in hypertrophic scar of rabbit ears, and the possibility of hypertrophic scar treated by 15d-PGJ2. Methods Eighteen New Zealand white rabbits were used to establish the hypertrophic scar models on the rabbit ears. The wounds were created as follows: 2 cm × 3 cm wounds with total skin loses on the ventral side, 2wounds for each ear, total 72 wounds. The wounds were randomly divided into the 15d-PGJ2 treatment group and NS control group. A total of 20 μl 15d-PGJ2 or NS was injected into the ear scar once a day for 7 days. At the 14th and 21st day after the injection, 18 scars in each group were harvested. The expression levels of type Ⅰ collagen was detected by immunohistochemistry, fluorescence quantitative polymerase chain reaction (PCR) and Western blotting. Results Compared with the NS control group, the 15d-PGJ2-treated scars appeared to be smaller, softer, flatter and lighter in color. The expression of type Ⅰcollagen was mainly distributed in matrix, fibroblast cytoplasma and the vascular wall. The mRNA and protein levels of type Ⅰ collagen were significantly decreased in the 15d-PGJ2-treated group as compared with those in the NS control group at different time points (P < 0. 05). Conclusion 15d-PGJ2, the ligand of PPAR-γ, can reduce the expression of type Ⅰ collagen in hypertrophic scar of rabbit ears and plays an important role in the prevention and treatment of hypertrophic scar. It offers a new way for treating the hypertrophic scar clinically. Key words: Hypertrophic scar; PPAR-γ; Collagen

Bifidobacterium as an oral delivery carrier of oxyntomodulin for obesity therapy: inhibitory effects on food intake and body weight in overweight mice

Oxyntomodulin (OXM) is a gut hormone released from intestinal L cell. Synthetic OXM and its analog reduce food intake and body weight in both rodents and human beings by being administered intravenously. However, people find intravenous administration difficult because of its side effects and inconvenience. The aim of this study is to develop a novel oral delivery system for OXM and its analog using genetically engineered Bifidobacterium as the carrier. An OXM gene expression vector pBBADs-OXM for the Bifidobacterium genus was constructed. Human OXM sequence was fused with extracellular exo-xylanase (XynF) signal peptide (Xs) from Bifidobacterium longum under the control of the pBAD promoter. B. longum NCC2705 was transformed with the recombinant plasmid pBBADs-OXM by electroporation, and the transformed B. longum was selected using MRS plates containing 60 microg ml(-1) ampicillin. The OXM expression in vitro was identified by western blot and enzyme-linked immunosorbent assay (ELISA) assay after L-arabinose induction. Overweight BALB/c mice were treated with B. longum transformed with OXM after 0.2% L-arabinose induction every day for 4 weeks to investigate the effects of OXM-transformed B. longum on food intake and body weight by oral administration. The B. longum transformed with the green fluorescent protein (GFP) gene was used as negative control; orlistat, a gastrointestinal lipase inhibitor, was used as positive control; Normal saline (NS, 0.9% saline) was used as blank control. The food intakes of each group were measured every day, and body weights were measured once a week. Normal BALB/c (2 months old) mice were treated with OXM-transformed B. longum after induction by intragastric administration every day for 6 days to reveal the mechanism of transformed B. longum, with OXM exerting its biological function by oral administration. Plasma OXM, plasma ghrelin and the OXM of intestinal contents were detected by the ELISA method. Plasma glucose and triglyceride levels were analyzed using the Automatic Biochemistry Analyzer. Transformed B. longum with OXM was selected and identified without biological and morphological alteration. An approximately 4-5 kDa OXM peptide was detected in both the supernatant and the cell pellet of transformed B. longum after L-arabinose induction in vitro. The food intake, body weight and blood triglyceride level of overweight mice treated with OXM-transformed B. longum were all significantly reduced compared with that of the GFP negative control group and NS control group (P<0.01). Interestingly, the plasma triglyceride level of the GFP group was significantly decreased compared with that of the NS control group (P<0.01). The OXM level in the intestinal contents of the OXM group was significantly increased compared with that of the GFP negative control group and the NS group (P<0.05). The plasma ghrelin level of the OXM group was significantly decreased compared with that of the GFP and NS groups (P<0.01). Unexpectedly, the ghrelin level of the GFP group was significantly increased compared with that of the NS control group (P<0.01). A novel oral delivery system of Bifidobacterium for human OXM has been successfully established. The expression of recombinant OXM can be detected in the supernatant and cell pellet of transformed B. longum. OXM-transformed B. longum reduces food intake, body weight and plasma lipid level in overweight mice by oral administration.

Study on murine Heps hepatoma tissue after mesenchymal stem cells inoculation

Objective To observe the local immue response and changes of angiogenic factors of tumor cells in Heps-bearing mice after mesenchymal stem cell (MSC) are administrated. And to explore the feasibility and safety of MSC for liver tumors therapy. Methods MSC were obtained through adherent culture method. Phe-notypes of MSC were analyzed by flow cytometry. MSC were labeled with DAPI in vitro. 54 Mice of 8 weeks of age with subcutaneously transplanted liver carcinomas were developed randomly. When the maximal diameters of the tumor reached 0.5 - 0.8cm, they were divided into three groups randomly: MSC group, DAPI group and NS control group. 2 × 10~6 MSC and MSC marked by DAPI were administrated into the mice right rear back tumor tissue. The survival time of the tumor-bearing mice was recorded and the mean survival time was calculated. Immunohistochemical staining was performed to count CD4~+ T cells and CD8~+ T cells in the local tumor,as well as to examine the expression of vascular endothelial growth factor ( VEGF) in tumor cells. Results In the MSC group,the mean survival time was 45 d (95%CI;33 ～56 d) ,in the NS control group, the mean survival time was 33 d ( 95%CI : 28 ～ 37 d). There was a statistical significance in the difference between them ( P < 0.05). Immunohistochemical staining results showed as follow: the number of CD4~+ T cells and CD8~+ T cells in the MSC group decreased significantly in comparison with the NS control group at early stage. The expression of VEGF also decreased obviously in comparison with the NS control group and induced tumor cells necrosis at late stage. The survival time of MSC group was prolonged. Conclusion MSC can engraft in Heps-bearing tumor tissue, and inhibit T lymphocyte cellular immunity at early stage. It can reduce the number of CD4~+ T cells and CD8~+ T cells and promote tumor growth. MSC can down regulate VEGF expression and induce tumor cells necrosis at late stage. By this way,it can prolong the survival time of Heps-bearing mice. Key words: Mesenchymal stem cells; Cytokines; Vascular endothelial growth factors; Heps hepatoma

Scorpion venom polypeptide accelerate irradiated hematopoietic cells proliferation

Objective To study the effects of Scorpion venom polypeptide (SVP) on the irradiated hematopoietic progenitor cells and the initial research of its mechanism. Methods and materials (1) MTT array was used to select the effective concentration of SVP that had proliferate action on the irradiated early hematopoietic cells (K562), just like the doses of experiment in vitro; (2) The male BALB/c mice were divided into NS control group, SVP IV group and SVP V group. After treatment and sublethal irradiation, the C-KIT and IL-6Rα levels of bone marrow cells were detected by immunohistochemistry and tissue array; (3) The bone marrow cells of the normal BALB/c mice, given to SVP IV and SVP V after different action times respectively, were taken to extract the total proteins inside the cell, the phosphorylated STAT3 protein levels in JAK-STAT signal transduction pathway were detected by Western blot array. Results (1) 30 mg/L SVP IV has an obvious effect to accelerate K562 cell proliferation; (2) The C-KIT and IL-6Rα expression on bone marrow cell surfaces in SVP IV and SVP V groups were negative (control with the saline group, p > 0.05); (3) The phosphorylated STAT3 protein levels in bone marrow cells of SVP IV group had a rise-and-fall trend within 30 min, while the test of SVP V group showed that the phosphorylated STAT3 protein levels obviously elevated after 30 min. Conclusions The results show that certain SVP IV concentration can protect the hematopoietic progenitor cells after irradiation, and the underlying mechanism of SVP accelerating the hematopoietic recovery in irradiated mice may be related to the activation of the JAK-STAT signal pathway.

Platelet-Derived Microparticles Induce Angiogenesis In Vitro and In Vivo.

Objective: An attempt was made to investigate the effect of platelet-derived microparticles (PMPs) on the angiogenesis.Methods: Thrombin was adopted to activate the platelets to release PMPs. Flow cytometry(FCM)was adopted to evaluate the efficiencies of different concentrations of thrombin to produce PMPs and BCA was adopted to evaluate the content of PMPs. By the carrier of human umbilical vein cell line ECV-304 cultivated in vitro, investigate the effect of PMPs on the proliferation and apoptosis of human umbilical vein endothelial cells using MTT and FCM. PMPs were put into CAM and observe the effects of PMPs on angiogenesis in Chick embryo chorioallantoic membrane (CAM).Results: The efficiencies of PMPs activated by 1.0U/ml thrombin were 50.1%; PMPs induced proliferation of human umbilical vein cell line ECV-304 in a dose dependent manner. At the concentration of 40ug/ml PMPs, the proliferation rate of human umbilical vein cell line ECV-304 was as 1.8±0.3 times as control and there was no difference with the group of vascular endothelial growth factor (VEGF),which the proliferation rate was 1.9±0.5 times vs. control, p > 0.05;PMPs inhibited human umbilical vein cell line ECV-304 apoptosis. Compared with control group (apoptosis rate 9.4%±0.5%), apoptosis rate of PMPs (40μg/ml) is 3.9%±0.4%, which was significantly reduced, p<0.05. The addition of VEGF (10μl/ml) did not successfully prevented apoptosis of human umbilical vein cell line ECV-304 (apoptosis rate 8.0%±0.8%);After 72 h of incubation, showing an implant of PMPs by allantoic vessels developing radially towards it (implant) in a 'spoked-wheel' pattern, at the concentration of 80μg/ml PMPs, number of vessel ramification is 112.5±11.31 and vessel area/CAM area is (6.19±1.29)%, compared with the VEGF(p>0.05). But there are not localized allantoic vessels developing in the NS control group(P<0.05).Conclusion: 1.0U/ml thrombin activated platelet could get the best efficiency of PMPs, which could stimulate proliferation of human umbilical vein cell line ECV-304 and inhibit its apoptosis and PMPs have certain promotive effect on the formation of capillary in chick chorioallantoic membranes.

Girl – lass or curl?

One of the ways to investigate the mental lexicon is to use word association tests. Empirical studies comparing associations by children and adults have indicated a tendency for children to give syntagmatic responses, whereas adults give paradigmatic responses. In order to investigate lexical development in L2 acquisition of Swedish we collected data from two groups of students, one in MalmÖ, Sweden and one in Melbourne. Part of the Melbourne group also took the association test in their L1 six months later. Native speakers were used as a control group. The results demonstrate that learners in general tend to focus more on form than content compared to native speakers. This trend was particularly strong for the L2 group in Melbourne who also exhibited more variation in their responses compared to the L2 group in Sweden and the NS control group.

Girl – lass or curl?

One of the ways to investigate the mental lexicon is to use word association tests. Empirical studies comparing associations by children and adults have indicated a tendency for children to give syntagmatic responses, whereas adults give paradigmatic responses. In order to investigate lexical development in L2 acquisition of Swedish we collected data from two groups of students, one in MalmÖ, Sweden and one in Melbourne. Part of the Melbourne group also took the association test in their L1 six months later. Native speakers were used as a control group. The results demonstrate that learners in general tend to focus more on form than content compared to native speakers. This trend was particularly strong for the L2 group in Melbourne who also exhibited more variation in their responses compared to the L2 group in Sweden and the NS control group.

Role of norepinephrine in development of short-term myocardial hibernation

To investigate the role of norepinephrine in the development of short-term myocardial hibernation. Hearts were removed from rats and set up as isometrically beating or short-term hibernation models. The hearts were perfused with modified Krebs-Henseleit buffer under a controlled perfusion pressure. The myocardial ultrastructure was examined, and the content of ATP, phosphocreatine, and glycogen in myocardium, the extent of myocyte apoptosis, and the amount of Bcl-2 and Bax products were determined after 120-min ischemia assessed by TUNEL and immunocytochemistry. There was no significant difference between the reserpinized hearts and the NS control group with respect to heart function, myocardial ultrastructure, ATP, phosphocreatine, or glycogen content, myocyte apoptosis, or amount of Bax or Bcl-2 products. However, relative to the normal saline group, in the norepinephrine-treated hearts, heart function, and myocardial ultrastructure deteriorated significantly, apoptosis and amount of Bax product increased significantly, and the ATP, phosphocreatine, and glycogen content decreased significantly, as did the amount of Bcl-2 product. Myocardial norepinephrine does not contribute to the development of short-term hibernation, but that exogenous NE can induce progressive decreases in coronary flow and cardiac performance, which might result from the increases in apoptosis and necrosis. Norepinephrine may be an important factor in the deterioration of myocardial structure and function during hibernation, and that anti-adrenergic treatment may be helpful for the development and sustainment of short-term myocardial hibernation.

Influence of Lamotrigine and Topiramate on MDR1 Expression in Difficult‐to‐Treat Temporal Lobe Epilepsy

Overexpression of the multiple drug resistance gene 1 (MDR1) was quantified in brain tissue from Coriaria lactone (CL)-kindled Sprague-Dawley (SD) rats after treatment with lamotrigine (LTG) or topiramate (TPM) and compared with that found in rats treated with carbamazepine (CBZ) and valproate (VPA). Twenty-five CL-kindled SD rats were randomized into five groups (n = 5 for each group) to receive once-daily feeding of CBZ, VPA, TPM, and LTG as the monotherapy equivalent of maximum human adult dosage, or normal saline (NS control) for 1 month. The expression of P-gp in brain tissues of all rats was quantified by using an image analysis and measuring system (Image Pro-plus 4.0). Mean area and mean integrated optical density (mean IOD) of P-gp expression were calculated. In addition, the changes in seizure severity were analyzed via video-camera monitoring. A significant decrease in the number and duration of seizures with antiepileptic drug (AED) treatment was observed in the TPM and LTG groups. The mean area and mean IOD of P-gp expression were highest in the CBZ group and next highest in the VPA group; much lower values were measured in the TPM and LTG groups, and the lowest in the NS control group (p < 0.05). TPM and LTG significantly inhibited seizures in this CL model. The expression of P-gp was not significantly increased by TPM or LTG treatment in this study.

Anti-endotoxin effect of lanthanum chloride in vivo: an experimental study of mice

Lanthanum is one of rare earth with extremely active chemical property and has been evidenced to possess antibacterial effect as well as the function of blocking calcium flux and regulating cellular immunity. Our previous studies showed that lanthanum could affect the biological activity of LPS and inhibit the activity in vitro. In this study, we explored the anti-LPS effects of lanthanum chloride in vivo so as to provide evidence in searching for new anti-endotoxic agents for the prevention and treatment of endotoxemia. (1) 96 BALB/c mice were divided into 2 groups: experimental group including 84 mice injected intraperitoneally with 17.5 mg/kg, LD(50) dose, of LPS mixed with lanthanum chloride of the dosages of 1 mg/kg, 2 mg/kg, 5 mg/kg, 10 mg/kg, 20 mg/kg, 40 mg/kg, and 80 mg/kg respectively; and control group including 12 mice injected intraperitoneally with 17.5 mg/kg of LPS. The mortality rates of different mice within 7 days were observed so as to observe the protective effect of lanthanum chloride. (2) 40 BALB/c mice were randomly divided into 2 group 2: experimental group injected intraperitoneally with lanthanum chloride of the dosages 10 mg/kg for 3 days and then injected with 1 LD(50) dosage of LPS 30 minutes after the last injection of lanthanum chloride of the dosages 10 mg/kg; and control group injected intraperitoneally with normal saline for 3 days and then with 1 LD(50) dosage of LPS 30 minutes after the last injection of normal saline. The mortality rates of different mice within 7 days were observed. (3) 40 BALB/c mice were randomly divided into 4 groups: LPS group, injected intraperitoneally with LPS of sublethal dosage (12.5 mg/kg), lanthanum chloride treatment group, injected intraperitoneally with LPS of sublethal dosage 1 hour after the venous injection of 10 mg/kg lanthanum chloride, lanthanum chloride control group, injected intravenously with 10 mg/kg lanthanum chloride, and NS control group, injected intraperitoneally with NS. Four hours after the intraperitoneal injection blood sample were collected to detect the plasma tumor necrosis factor-alpha (TNFalpha) and liver and thymus tissues were collected to examine the expression of TNFalpha mRNA and apoptosis of thymocytes by Rt-PCR and flow cytometry so as to observe the effects of lanthanum chloride on LPS-induced reaction in vivo. The mortality rates of the mice administrated with LD(50) dosage of LPS combined with 5, 10, and 20 mg/kg lanthanum chloride were 0, 0, and 8% respectively, all significantly lower than that of the control group (67%, all P < 0.01). The mortality rate of the LPS-challenged mice that were pretreated with 10 mg/kg of lanthanum chloride was 20%, significantly lower than that of the control group (55%, P < 0.05). (2) In the mice with endotoxemia that were pretreated with lanthanum chloride the plasma TNFalpha level was 0.44 +/- 0.22 ng/ml and the TNFalpha mRNA expression in liver was (3.93 +/- 0.62) x 10(5) copies/ micro g RNA, both significantly lower than those of the mice with endotoxemia without pretreatment of lanthanum chloride, 0.99 +/- 0.24 ng/ml and (1.9 +/- 0.33) x 10(7) copies/ micro g RNA (both P < 0.001). The percentage of DNA fragmentation of thymocytes in the mice challenged with LPS and pretreated with lanthanum chloride was 14.77% +/- 1.0%, significantly lower than that of the untreated mice (55.38% +/- 3.88%, P < 0.001), the percentage of hypodiploidy in thymocytes of the mice challenged with LPS was 15.56% +/- 0.59%, significantly higher than that of the lanthanum chloride treated mice (6.05% +/- 0.71%, P < 0.001). (3) Morphologic observation showed that pathological changes of the thymocytes and liver and lung tissues were remarkably milder in the lanthanum chloride-treated mice than in the mice challenged only by LPS. (1) Lanthanum chloride can bind LPS and reduce its toxicity, which shows protective effects on mice challenged by lethal dose LPS. (2) Lanthanum chloride can greatly decrease the secretion of TNFalpha and TNFalpha mRNA expression in the mice the secretion of TNFalpha and TNFalpha mRNA expression in the mice challenged with LPS. Furthermore, LPS-induced apoptosis of thymocyte and damage of liver and lungs are inhibited by lanthanum chloride.

Effects of Hypertonic Saline and Dextran 70 on Cardiac Diastolic Function after Hemorrhagic Shock

Background. A bolus of 7.5% NaCl-6% Dextran 70 (HSD) is effective in resuscitating hypovolemic shock. Common hemodynamic findings with HSD are restoration of cardiac output, increased blood pressure, and improvement of peripheral circulation. However, the effect of HSD upon cardiac function is still controversial. In our previous study, when HSD did not improve cardiac contractility, it was speculated that it might affect cardiac diastolic function without a change in contractility. Therefore, we studied the effects of HSD on cardiac diastolic function. Methods. Hemorrhagic shock was created by exsanguination of 31.4 ± 0.9 ml/kg (NS group) or 29.0 ± 3.6 ml/kg (HSD group). Then mean BP was maintained at 50 mm Hg for 30 min in both groups. The HSD group ( n = 6) received HSD (4 ml/kg) and the NS (control) group ( n = 5) received normal saline (40 ml/kg) after the shock. Cardiac diastolic functions were measured in both groups using the peak negative dP/ dt and the left ventricular end-diastolic pressure-volume relationship (EDPVR) during the experimental period: before shock, immediately, and 2 h after resuscitation. Results. Hemodynamic parameters in both groups demonstrated similar changes throughout the experimental period. The peak negative dP/ dt, stiffness constant, and elasticity obtained by EDPVR did not differ significantly between the two groups. Conclusion. HSD seems to be an effective resuscitation fluid after hemorrhagic shock because the volume of HSD required to maintain circulation is significantly smaller than that of normal saline. However, our data revealed that HSD does not change cardiac diastolic function after hemorrhagic shock.

Effects of Hypertonic Saline and Dextran 70 on Cardiac Diastolic Function after Hemorrhagic Shock

<h2>Abstract</h2> <i>Background.</i> A bolus of 7.5% NaCl-6% Dextran 70 (HSD) is effective in resuscitating hypovolemic shock. Common hemodynamic findings with HSD are restoration of cardiac output, increased blood pressure, and improvement of peripheral circulation. However, the effect of HSD upon cardiac function is still controversial. In our previous study, when HSD did not improve cardiac contractility, it was speculated that it might affect cardiac diastolic function without a change in contractility. Therefore, we studied the effects of HSD on cardiac diastolic function. <i>Methods.</i> Hemorrhagic shock was created by exsanguination of 31.4 ± 0.9 ml/kg (NS group) or 29.0 ± 3.6 ml/kg (HSD group). Then mean BP was maintained at 50 mm Hg for 30 min in both groups. The HSD group (<i>n</i> = 6) received HSD (4 ml/kg) and the NS (control) group (<i>n</i> = 5) received normal saline (40 ml/kg) after the shock. Cardiac diastolic functions were measured in both groups using the peak negative <i>dP</i>/<i>dt</i> and the left ventricular end-diastolic pressure-volume relationship (EDPVR) during the experimental period: before shock, immediately, and 2 h after resuscitation. <i>Results.</i> Hemodynamic parameters in both groups demonstrated similar changes throughout the experimental period. The peak negative <i>dP</i>/<i>dt</i>, stiffness constant, and elasticity obtained by EDPVR did not differ significantly between the two groups. <i>Conclusion.</i> HSD seems to be an effective resuscitation fluid after hemorrhagic shock because the volume of HSD required to maintain circulation is significantly smaller than that of normal saline. However, our data revealed that HSD does not change cardiac diastolic function after hemorrhagic shock.

Evidence for mitochondrial K ATP channels as effectors of human myocardial preconditioning.

Sublethal periods of ischemia preceding a prolonged interval of ischaemia protect the myocardium. This myocardial preconditioning (PC) appears to be effected by KATP channels. These channels occur both in the sarcolemma and the mitochondrial membrane. We investigated whether mitochondrial KATP channels are the end-effector of PC in the human myocardium. Right atrium specimens obtained from patients undergoing cardiac surgery were prepared and incubated in buffer solution at 37 degrees C. After 30-min stabilisation, the muscles were made ischemic for 90 min and then reperfused for 120 min. The preparations were randomised into eight experimental groups (n = 6/group): (1) Aerobic control--incubated in oxygenated buffer for 210 min, (2) ischemia alone--90 min ischemia followed by 120 min reperfusion, (3) PC--preconditioned with 5 min ischemia/5 min reperfusion, (4) Glibenclamide (10 microM) in the incubation media for 10 min before PC, (5) 5-hydroxydecanoate (5-HD, MitoKATP blocker, 1 mM) in the incubation media for 10 min before PC, (6) HMR 1883 (SarcKATP blocker, 10 microM) in the incubation media for 10 min before PC, (7) Pinacidil (0.5 mM) in the incubation media for 10 min before ischemia, and (8) Diazoxide (MitoKATP opener, 0.1 mM) in the incubation media for 10 min before ischemia. Creatinine kinase leakage into the medium (CK, IU/g wet wt) and MTT reduction (OD/mg wet wt.), an index of cell viability, were assessed at the end of the experiment. Ischemia alone resulted in a significant increase in CK leakage (8.01 +/- 0.35) and decrease in MTT (0.15 +/- 0.01) from the values seen in the aerobic control (2.24 +/- 0.52 and 0.78 +/- 0.10 respectively, P < 0.05 in both instances). PC fully reversed the effect of ischemia (CK = 2.97 +/- 0.31 and MTT = 0.61 +/- 0.05; P < 0.05 vs. ischemia alone group but P = NS vs. aerobic control group). Both Glibenclamide and 5-HD abolished the protection induced by PC (CK = 6.23 +/- 0.5 and 7.84 +/- 0.64; MTT = 0.18 +/- 0.03 and 0.13 +/- 0.02, respectively, P < 0.05 vs. PC), but interestingly, the protective effect of PC was not abolished by HMR 1883 (CK = 2.85 +/- 0.24 and MTT = 0.58 +/- 0.05, P = NS vs. PC). Diazoxide mimicked the protective effect of PC (CK = 3.56 +/- 0.32 and MTT = 0.58 +/- 0.02, P = NS vs. PC), however pinacidil exhibited less protection than PC (CK = 4.02 +/- 0.16 and MTT = 0.30 +/- 0.02, P < 0.05 vs. PC). These studies demonstrate that KATP channels are the end-effectors of ischemic preconditioning and that protection is mediated by mitochondrial KATP channels in human right atrial myocardium.

Accelerated release and production of orphanin FQ in brain of chronic morphine tolerant rats

Orphanin FQ has been shown to possess anti-opioid activity at supraspinal level. Our previous work revealed that chronic morphine tolerance could be reversed by intracerebroventricular (i.c.v.) injection of OFQ IgG to rats. In this study, we used radioimmunoassay (RIA) to assess the changes of Orphanin FQ immunoreactivity (OFQ-ir) in cerebroventricular perfusate, periaqueductal gray (PAG) and amygdala of rats made tolerance to morphine (10–60 mg/kg, s.c., t.i.d., for 5 days). The results indicated that: (1) In rats administrated with morphine for 3 and 5 days, the content of OFQ-ir in cerebroventricular perfusate increased by 25% and 52% over the NS control group. (2) The content of OFQ-ir in PAG of rats receiving 1d, 3d and 5d injections of morphine showed an increase of 17%, 48% and 81% respectively over NS group. (3) The content of OFQ-ir in amygdala of rats given 3d and 5d of morphine showed a 36% and 55% increase compared with corresponding control group. It is suggested that continuous use of high doses of morphine accelerated the release and biosynthesis of OFQ in rat brain to antagonize the effect of opioids, which may play a role in the development of morphine tolerance, and that brain OFQ may serve as a delayed negative feedback control on opioid analgesia.

Does Calcium Chloride Help Restore Maternal Blood Pressure and Uterine Blood Flow During Hemorrhagic Hypotension in Hypermagnesemic Gravid Ewes?

Magnesium sulfate worsens maternal hypotension and fetal oxygenation during hemorrhage in gravid ewes. The purpose of this study was to determine whether calcium chloride administration is a useful adjunct to blood transfusion during hemorrhagic hypotension in hypermagnesemic gravid ewes. Sixteen experiments were performed in eight chronically instrumented animals between 0.8 and 0.9 of timed gestation. The experimental sequence included (a) T = 0: magnesium sulfate 4 g IV; (b) T = 5: infusion of magnesium sulfate 4 g/h IV; (c) T = 90: maternal hemorrhage 20 mL/kg over 55 min; (d) T = 147: calcium chloride 10 mg/kg or normal saline (NS-control) 0.1 mL/kg IV; (e) T = 160: transfusion of collected maternal blood over 55 min. Magnesium sulfate alone slightly decreased maternal mean arterial pressure (P = 0.002) and increased uterine blood flow (P = 0.0001) in both groups before hemorrhage. During hemorrhage, maternal mean arterial pressure, cardiac output, and uterine blood flow, and fetal PO2 and pH all decreased sharply (P = 0.0001). Cardiac output increased (P = 0.0005) modestly just after the intravenous bolus of calcium chloride. Maternal mean arterial pressure was significantly higher (P = 0.03) during transfusion in the calcium chloride group than in the NS-control group, but only after mean arterial pressure was near baseline measurements. Maternal uterine blood flow and fetal PO2 and pH responses over time were similar in the two groups. We conclude that intravenous administration of calcium chloride (10 mg/kg) transiently increased cardiac output during hemorrhagic hypotension and slightly increased mean arterial pressure during transfusion in hypermagnesemic gravid ewes.(ABSTRACT TRUNCATED AT 250 WORDS)