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1.
This study analyzes both cell migration and exudation responses elicited by substance P (SP) in the mouse pleural cavity. SP caused, 4 h after its administration into the mouse pleural cavity, a dose-related recruitment of leukocytes (ED50 = 14.2 nmol), mainly due to mononuclears. Leukocytes peaked between 2 and 4 h, being followed by a slight decay that remained elevated for up to 24 h. Exudation, although small, was significantly elevated from 2 to 96 h after. NK1 (FK 888) or NK3 (SR 142801), but not NK2 (SR 48968) tachykinin receptor antagonists, significantly inhibited cell migration. HOE 140 and NPC 17731, bradykinin B2 receptor antagonists, caused graded inhibition of cell influx (ID50s of 0.03 and 0.04 pmol), but des-Arg9-Leu8-BK, B1 receptor antagonist, had no effect. The nitric oxide inhibitors L-NOARG and L-NAME, but not D-NAME, significantly inhibited SP-induced pleurisy. Pretreatment of the animals with indomethacin, dexamethasone, terfenadine, theophylline or salbutamol produced significant inhibition of the inflammatory parameters, whereas cromolyn only inhibited exudation. These results indicate that intrapleural injection of SP in mice elicit a long-lasting inflammatory reaction that is characterized by the participation of nitric oxide, kinins, cyclooxygenase metabolites and histamine. Antiasthmatic drugs such as theophylline, salbutamol, dexamethasone, and, to a lesser extent cromolyn, also markedly inhibit this inflammatory reaction. These results provide clear evidence supporting the role played by SP in neurogenic inflammation.  相似文献   

2.
BACKGROUND: The model of pleurisy induced by carrageenan exhibits a biphasic response (4 and 48 h) and permits the quantification of exudate, cell migration and certain enzymes such as myeloperoxidase (MPO) and adenosine-deaminase (ADA) that are markers of activated leukocytes. AIMS: The present study evaluates whether there exists, in the pleurisy model, a significant inhibition of ADA and MPO enzymes, leukocyte kinetics and other markers of inflammation [nitric oxide (NO) levels, exudation] caused by methotrexate treatment by the intraperitoneal (i.p.) route. METHODS: The pleurisy was induced by carrageenan (1%) in mice, and the parameters were analyzed 4 and 48 h after. RESULTS: After the induction of inflammation (4 h), methotrexate (20 mg/kg, i.p., 24 h before pleurisy induction) inhibited the leukocyte infiltration (p < 0.05), NO levels and MPO activity (p < 0.01), but not ADA activity and fluid leakage (p > 0.05). Regarding the second phase of pleurisy (48 h), methotrexate (40 mg/kg, i.p., 0.5 h before pleurisy induction) inhibited the leukocyte infiltration (p < 0.05), fluid leakage, NO levels (p < 0.01), and ADA and MPO activity (p < 0.05). CONCLUSIONS: These findings support the evidence that the acute administration of methotrexate has an important systemic anti-inflammatory activity in the studied inflammatory model. This effect was due to a significant inhibition on both neutrophil and mononuclear cells, being less marked in relation to exudation 48 h after. In relation to the enzymes studied and to NO levels, the findings support the evidence that methotrexate inhibits both enzymes (MPO and ADA) from leukocytes at the site of injury, thus reflecting the activation of both neutrophils and lymphocytes, respectively. Furthermore, the inhibiting effect on NO in both phases of pleurisy induced by carrageenan (4 and 48 h) indicates that methotrexate acts on constitutive and/or inducible NO synthases by means of different cells of the pleural cavity.  相似文献   

3.
4.
Damage to the airway epithelium is common in asthma. Corticosteroids induce apoptosis in and suppress proliferation of airway epithelial cells in culture. Whether apoptosis contributes to impaired epithelial cell repair after injury is not known. We examined whether corticosteroids would impair epithelial cell migration in an in vitro model of wound closure. Wounds (approximately 0.5-1.3 mm2) were created in cultured 1HAEo- human airway epithelial cell monolayers, after which cells were treated with up to 10 microM dexamethasone or budesonide for 24 h. Cultured cells were pretreated for 24 or 48 h with dexamethasone to observe the effect of long-term exposure on wound closure. After 12 h, the remaining wound area in monolayers pretreated for 48 h with 10 microM dexamethasone was 43+/-18% vs. 10+/-8% for untreated control monolayers. The addition of either corticosteroid immediately after injury did not slow closure significantly. After 12 h the remaining wound area in monolayers treated with 10 microM budesonide was 39+/-4% vs. 43+/-3% for untreated control monolayers. The proportion of apoptotic epithelial cells as measured by terminal deoxynucleotidyltransferase-mediated dUTP biotin nick end labeling both at and away from the wound edge was higher in monolayers treated with budesonide compared with controls. However, wound closure in the apoptosis-resistant 1HAEo-.Bcl-2+ cell line was not different after dexamethasone treatment. We demonstrate that corticosteroid treatment before mechanical wounding impairs airway epithelial cell migration. The addition of corticosteroids after injury does not slow migration, despite their ability to induce apoptosis in these cells.  相似文献   

5.
Fröde TS  Souza GE  Calixto JB 《Cytokine》2001,13(3):162-168
We describe here the modulation caused by intrapleural (i.pl.) injection of the cytokines TNF-alpha and IL-1beta and their specific antibodies in the early (4 h) and late (48 h) inflammatory responses caused by injection of carrageenan (Cg) into the mouse pleural cavity. The antibodies against TNF-alpha and IL-1beta, when injected 30 min prior to Cg, reduced, in a graded and significant manner, both exudation and cell migration in the early (4 h) phase, while they potentiated or had no effect in the late (48 h) phase of Cg response. The natural IL-1 receptor antagonist IL-1RA, given 30 min prior to Cg, reduced the exudation by about 50% and abolished the total and differential cell migration in the early (4 h) and late (48 h) phases of the Cg responses. The i.pl. injection of TNF-alpha or IL-1beta, 5 min prior to Cg, caused graded increase in the exudation of the early (4 h) and late (48 h) phases of the Cg-induced inflammatory responses. In contrast, these treatments markedly reduced the total and differential cell migration at 4 h, while having little or no effect on the late (48 h) phase of the Cg pleurisy. These findings extend previous results and demonstrate that the pro-inflammatory cytokines TNF-alpha and IL-1beta have a critical role in controlling both cell migration and exudation caused by injection of Cg in the mouse pleural cavity. Together, these findings may be relevant to the understanding of the mechanisms involved in airway inflammatory responses.  相似文献   

6.
BACKGROUND: Abdominal sepsis induces a local production of proinflammatory mediators that may trigger both septic shock and organ-system dysfunction. AIMS: The present study analyzed exudation, cell migration, and CD11a and CD18 subset cells of both local and systemic responses induced by fecal peritonitis in mice. METHODS: Animals were anesthetized and, after performing a midline incision in the abdomen, the cecum was ligated and punctured twice with a needle. Sham-operated animals were included. Some groups were previously treated with Evans blue dye (intravenously) to further evaluate the amount of tissue and abdominal cavity leakages. RESULTS: Fecal peritonitis triggered a local inflammatory reaction with an increased number of leukocytes and exudation between 6 and 48 h (p < 0.01). Although CD11a/CD18-positive cells in the abdomen peaked after 24h, a significant decrease of them was detected after 48 h (p < 0.05). At the studied period of time (6-48 h), different degrees of exudation in several organs occurred, whereas a significant late recruitment (24 h) of CD11a/CD18 cells into the lungs was observed. CONCLUSIONS: In this model, cell migration and exudation at the site of injury occurred in parallel. However, in the lungs, the recruitment of leukocytes that express CD11a/CD18 adhesion molecules constitutes a non-dependent event in relation to fluid leakage accumulation at this site.  相似文献   

7.
Long-term culture of hepatocytes has been challenged by the loss of differentiated functions. In particular, there is a rapid decline in cytochrome P450 (CYP). In this study, we cocultured rat hepatocytes with 3T3 fibroblasts for 10 days, and examined hepatocyte viability, morphology, and expression of CYP3A. Terfenadine was incubated with the cultures, and its biotransformation was quantitatively analyzed by HPLC. Terfenadine is metabolized by two major pathways:C-hydroxylation to an alcohol metabolite which is further oxidized to a carboxylic acid, andN-dealkylation to azacyclonol. In rat liver, only theN-dealkylation pathway appears to be mediated by CYP3A since anti-rat CYP3A antibody inhibited azacyclonol but not alcohol metabolite formation in incubations of terfenadine with liver microsomes. Freshly isolated rat hepatocytes were seeded on top of confluent 3T3 cells. Cultures were maintained in Williams' E medium supplemented with 10% fetal bovine serum and either 0.1 mol/L or 5 mol/L dexamethasone. In pure hepatocyte cultures, viability, as determined by lactate dehydrogenase (LDH) activity, decreased steadily to less than 30% of initial levels by day 10. In cocultures, LDH activity remained high and was 70% of initial levels on day 10. The half-life of terfenadine disappearance was optimally maintained in cocultures treated with 5 mol/L dexamethasone, and was associated with the increased formation of azacyclonol. On day 5, nearly 50% of added 5 mol/L terfenadine was converted to azacyclonol within 6 h, whereas the conversion was only 4% on day 1. Western and RNA-slot blot analyses confirmed that treatment with 5 mol/L dexamethasone induced CYP3A mRNA expression and CYP3A protein expression. This coculture system could offer a useful approach in the study of drugs and xenobiotics metabolized by CYP3A.Abbreviations BSA bovine serum albumin - CYP cytochrome P450 - DMSO dimethyl sulfoxide - LDH lactate dehydrogenase - PCN pregnenolone-16-carbonitrile - SDS sodium dodecyl sulfate - SSC saline sodium citrate  相似文献   

8.
Both phosphorus (P) deficiency and aluminum (Al) toxicity induce root exudation of carboxylates, but the relationship between these two effects is not fully understood. Here, carboxylate exudation induced by Al in Lupinus albus (white lupin) was characterized and compared with that induced by P deficiency. Aluminum treatments were applied to whole root systems or selected root zones of plants with limited (1 microM) or sufficient (50 microM) P supply. Aluminum stimulated citrate efflux after 1-2 h; this response was not mimicked by a similar trivalent cation, La(3+). P deficiency triggered citrate release from mature cluster roots, whereas Al stimulated citrate exudation from the 5- to 10-mm subapical root zones of lateral roots and from mature and senescent cluster roots. Al-induced citrate exudation was inhibited by P limitation at the seedling stage, but was stimulated at later growth stages. Citrate exudation was sensitive to anion-channel blockers. Al treatments did not affect primary root elongation, but inhibited the elongation of lateral roots. The data demonstrate differential patterns of citrate exudation in L. albus, depending on root zone, developmental stage, P nutritional status and Al stress. These findings are discussed in terms of possible functions and underlying mechanisms.  相似文献   

9.
Lycopene, which is the predominant carotenoid in tomatoes and tomato-based foods, may protect humans against various cancers. Effects of lycopene on the adhesion, invasion, migration, and growth of the SK-Hep1 human hepatoma cell line were investigated. Lycopene inhibited cell growth in dose-dependent manners, with growth inhibition rates of 5% and 40% at 0.1 microM and 50 microM lycopene, respectively, after 24 hrs of incubation. Similarly, after 48 hrs of incubation, lycopene at 5 microM and 10 microM decreased the cell numbers by 30% and 40%, respectively. Lycopene decreased the gelatinolytic activities of both matrix metalloproteinase (MMP)-2 and MMP-9, which were secreted from the SK-Hep1 cells. Incubation of SK-Hep1 cells with 110 microM of lycopene for 60 mins significantly inhibited cell adhesion to the Matrigel-coated substrate in a concentration-dependent manner. To study invasion, SK-Hep1 cells were grown either on Matrigel-coated Transwell membranes or in 24-well plates. The cells were treated sequentially for 24 hrs with lycopene before the start of the invasion assays. Cell growth and death were assessed under the same conditions. The invasion of SK-Hep1 cells treated with lycopene was significantly reduced to 28.3% and 61.9% of the control levels at 5 microM and 10 microM lycopene, respectively (P < 0.05). In the migration assay, lycopene-treated cells showed lower levels of migration than untreated cells. These results demonstrate the antimetastatic properties of lycopene in inhibiting the adhesion, invasion, and migration of SK-Hep1 human hepatoma cells.  相似文献   

10.
Fröde TS  Souza GE  Calixto JB 《Cytokine》2002,17(3):149-156
This study evaluates the effects of intrapleural (i.pl.) injection of interleukin (IL-6) and IL-10 and their specific antibodies on the early (4 h) and late (48 h) inflammatory responses caused by carrageenan (Cg) injected into the mouse pleural cavity. The i.pl. injection of IL-6, 5 min prior to Cg, reduced in a dose-dependent and significant manner, the exudation and total and differential leukocyte migration according to assessment in both the early (4 h) and the late (48 h) phases of Cg inflammatory response (P<0.01). Intrapleural injection of IL-10, 5 min prior to i.pl. injection of Cg, resulted in a significant inhibition of the early phase (4 h) (P<0.01), but had no significant effect in relation to the late (48 h) phase of Cg response. The antibodies anti-IL-6 (given i.pl. 30 min prior to Cg) caused a significant decrease in both total and differential leukocyte influx, but significantly increased exudation according to assessment 4 h after pleurisy induction by Cg (P<0.01). In contrast, anti-IL-10 antibody caused graded and marked increase of both total and differential leukocyte influx and also increased fluid leakage as assessed 4 h after Cg injection (P<0.01). In the late phase (48 h) these antibodies increased the inflammatory parameters (anti-IL-6) studied or had no effect (anti-IL-10). Taken together, the current results confirm and extend previous data from the literature by showing that IL-6 and IL-10 regulate several signs of inflammatory response, here characterized by marked inhibition of polymorphonuclear cell influx and blockage of fluid leakage to the site of Cg-induced pleurisy in the mouse.  相似文献   

11.
The effect of 13-hydroxyoctadeca-9,11-dienoic acid (13-HODE), a major lipoxygenase product of endothelial cell linoleic acid metabolism on thrombin-induced platelet thromboxane B2 (TxB2), and 12-hydroxyeico-satetraenoic acid (12-HETE) production was evaluated. 13-HODE inhibited thrombin-induced TxB2 production in human platelets in a concentration-dependent manner. At concentrations of 10 and 30 microM, 13-HODE inhibited TxB2 production by 28 +/- 8% (1SE, n = 5; P less than 0.05) and 48 +/- 6% (P less than 0.01) respectively. 13-HODE (30 microM) also inhibited the production of platelet hydroxyheptadecatrienoic acid (38 +/- 5%, P less than 0.01). A concomitant stimulation of 12-HETE production by 13-HODE was observed (25 +/- 5% and 49 +/- 22% over control values at 10 and 30 microM respectively, P less than 0.01). Our results demonstrate a differential effect of 13-HODE on thrombin stimulated platelet cyclooxygenase and lipoxygenase metabolites.  相似文献   

12.
Mast cell recruitment is implicated in many physiological functions and several diseases. It depends on microenvironmental factors, including hormones. We have investigated the effect of progesterone on the migration of HMC-1(560) mast cells toward CXCL12, a chemokine that controls the migration of mast cells into tissues. HMC-1(560) mast cells were incubated with 1 nM to 1 microM progesterone for 24 h. Controls were run without progesterone. Cell migration toward CXCL12 was monitored with an in vitro assay, and statistical analysis of repeated experiments revealed that progesterone significantly reduced cell migration without increasing the number of apoptotic cells (P = 0.0084, n = 7). Differences between progesterone-treated and untreated cells were significant at 1 microM (P < 0.01, n = 7). Cells incubated with 1 microM progesterone showed no rearrangment of actin filaments in response to CXCL12. Progesterone also reduced the calcium response to CXCL12 and Akt phosphorylation. Cells incubated with progesterone had one-half the control concentrations of CXCR4 (mRNA, total protein, and membrane-bound protein). Progesterone also inhibited the migration of HMC-1(560) cells transfected with hPR-B-pSG5 plasmid, which contained 2.5 times as much PR-B as the control. These transfected cells responded differently (P < 0.05, n = 5) from untreated cells to 1 nM progesterone. We conclude that progesterone reduces mast cell migration toward CXCL12 and that CXCR4 may be a progesterone target in mast cells.  相似文献   

13.
Brassica rapa L. plants were grown hydroponically for 5 or 6 weeks at 20°C and then half batches of plants were transferred to tanks in which the root temperature was lowered decrementally over 1 h to 7°C. Changes in nitrate uptake rate (NUR) and nitrate transfer from roots were studied in relation to transpiration and root pressure xylem exudation flow rates over a 48- or 72-h period. The response of plants following the root temperature decrease was biphasic. During phase 1, NUR and water and solute flow rates through the root decreased sharply. Coping mechanisms came into operation during phase 2, and tended to offset the effects of low temperature. The 3-h cold-treated roots exhibited a very low NUR but 48-h cold-treated roots partly recovered their ability to absorb nitrate. Transpiration rate decreased more slowly (during 24 h) than both root xylem exudation and parameters of root conductivity (during 6 h). Beyond these respective times, transpiration rate was balanced while root xylem exudation clearly increased, but without returning to the level of control plants. Nitrate transfer to the root xylem was strongly and rapidly affected by low root temperature, but the subsequent readjustment was such that no or little difference compared with the control was apparent after 48 h. Water and solute flows were strongly decreased when nitrate was replaced by chloride in the culture solution during exudation sampling. The major role of nitrate in root hydraulic conductivity and root xylem exudation is discussed.  相似文献   

14.
The impact of diacerein, an effective cartilage targeted therapy that is used in patients with osteoarthritis, on the development and progression of chronic inflammatory arthritis was evaluated in a tumor necrosis factor (TNF) transgenic mouse model (Tg197). The response to diacerein at 2, 20, or 60 mg/kg daily, as well as the comparative effects of other antiarthritis drugs including dexamethasone (0.5 mg/kg daily), methotrexate (1 mg/kg three times weekly) and an anti-TNF agent (5 mg/kg weekly), were assessed in the Tg197 mice. Treatment was initiated before the onset of arthritis and was continued for 5 weeks. A significant improvement in clinical symptoms was found in all three diacerein treated groups in comparison with untreated groups. Confirming these data, semiquantitative histopathologic analysis of the hind paws revealed a significant reduction not only in cartilage destruction but also in the extent of synovitis and bone erosion in diacerein treated groups in comparison with untreated groups. At the most effective dose tested (2 mg/kg daily), diacerein inhibited the onset of arthritis in 28% and attenuated the progression of arthritis in 35% of the Tg197 mice. Comparative analyses showed diacerein to be more potent than methotrexate but not as effective as dexamethasone or anti-TNF agents in suppressing the progression of the TNF mediated arthritis in this model. These results indicate that diacerein has a disease modifying effect on the onset and progression of TNF driven chronic inflammatory arthritis, suggesting that the prophylactic or therapeutic potential of diacerein in patients with RA should be further examined.  相似文献   

15.
The impact of diacerein, an effective cartilage targeted therapy that is used in patients with osteoarthritis, on the development and progression of chronic inflammatory arthritis was evaluated in a tumor necrosis factor (TNF) transgenic mouse model (Tg197). The response to diacerein at 2, 20, or 60 mg/kg daily, as well as the comparative effects of other antiarthritis drugs including dexamethasone (0.5 mg/kg daily), methotrexate (1 mg/kg three times weekly) and an anti-TNF agent (5 mg/kg weekly), were assessed in the Tg197 mice. Treatment was initiated before the onset of arthritis and was continued for 5 weeks. A significant improvement in clinical symptoms was found in all three diacerein treated groups in comparison with untreated groups. Confirming these data, semiquantitative histopathologic analysis of the hind paws revealed a significant reduction not only in cartilage destruction but also in the extent of synovitis and bone erosion in diacerein treated groups in comparison with untreated groups. At the most effective dose tested (2 mg/kg daily), diacerein inhibited the onset of arthritis in 28% and attenuated the progression of arthritis in 35% of the Tg197 mice. Comparative analyses showed diacerein to be more potent than methotrexate but not as effective as dexamethasone or anti-TNF agents in suppressing the progression of the TNF mediated arthritis in this model. These results indicate that diacerein has a disease modifying effect on the onset and progression of TNF driven chronic inflammatory arthritis, suggesting that the prophylactic or therapeutic potential of diacerein in patients with RA should be further examined.  相似文献   

16.
Extracellular fibrinolysis, controlled by the membrane-bound fibrinolytic system, is involved in cartilage damage and rheumatoid arthritis (RA) synovitis. Estrogen status and metabolism seem to be impaired in RA, and synoviocytes show receptors for estrogens. Our aims in this study were to evaluate in healthy and RA synoviocytes the effects of Raloxifene (RAL), a selective estrogen receptor modulator (SERM), on: proliferation; the components of the fibrinolytic system; and chemoinvasion. The effects of RAL were studied in vitro on synoviocytes from four RA patients and four controls. Proliferation was evaluated as cell number increase, and synoviocytes were treated with 0.5 microM and 1 microM RAL with and without urokinase-plasminogen activator (u-PA) and anti-u-PA/anti-u-PA receptor (u-PAR) antibodies. Fibrinolytic system components (u-PA, u-PAR and plasminogen activator inhibitor (PAI)-1) were assayed by ELISA with cells treated with 0.5 microM and 1 microM RAL for 48 h. u-PA activity was evaluated by zymography and a direct fibrinolytic assay. U-PAR/cell and its saturation were studied by radioiodination of u-PA and a u-PA binding assay. Chemoinvasion was measured using the Boyden chamber invasion assay. u-PA induced proliferation of RA synoviocytes was blocked by RAL (p < 0.05) and antagonized by antibodies alone. The inhibitory effect of RAL was not additive with u-PA/u-PAR antagonism. RA synoviocytes treated with RAL showed, compared to basal, higher levels of PAI-1 (10.75 +/- 0.26 versus 5.5 +/- 0.1 microg/10(6) cells, respectively; p < 0.01), lower levels of u-PA (1.04 +/- 0.05 versus 3.1 +/- 0.4 ng/10(6) cells, respectively; p < 0.001), and lower levels of u-PAR (11.28 +/- 0.22 versus 23.6 +/- 0.1 ng/10(6) cells, respectively; p < 0.001). RAL also significantly inhibited u-PA-induced migration. Similar effects were also shown, at least partially, in controls. RAL exerts anti-proliferative and anti-invasive effects on synoviocytes, mainly modulating u-PAR and, to a lesser extent, u-PA and PAI-1 levels, and inhibiting cell migration and proliferation.  相似文献   

17.
许欣  辛晓燕  李佳  刘海霞  魏翻艳 《生物磁学》2014,(13):2401-2404
目的:探讨人卵巢癌顺铂耐药细胞株CP70沉默S100A4基因后,CP70细胞对顺铂敏感性、凋亡及细胞迁移的影响。方法:设计并合成S100A4基因特异性的siRNA并转染入卵巢癌细胞CP70,48 h后应用RT-PCR和Western Blot检测在mRNA和蛋白水平siRNA对S100A4的影响,MTT法检测转染siRNA后卵巢癌细胞CP70对顺铂敏感性的变化。用流式细胞术检测顺铂(40μM)对转染S100A4 siRNA后对卵巢癌细胞CP70凋亡的影响,Transwell法观察siRNA抑制S100A4后对卵巢癌CP70迁移能力的影响。结果:与空白对照组、阴性对照组相比,S100A4siRNA转染组CP70细胞的S100A4基因和蛋白表达降低(P〈0.01)。MTT法检测顺铂敏感性发现S100A4 siRNA转染组CP70细胞顺铂敏感性增强。在顺铂刺激下,siRNA转染组细胞凋亡率高于其他各组,差异具有统计学意义(P〈0.05)。Transwell发现CP70细胞迁移能力明显下降(P〈0.05)。结论:S100A4 siRNA能够明显抑制CP70细胞S100A4的表达,从而增强细胞对顺铂的敏感性,促进细胞凋亡,减弱细胞的迁移能力。S100A4有望成为逆转卵巢癌铂类耐药的治疗靶点。  相似文献   

18.
19.
Fukuzawa M  Williams JG 《FEBS letters》2002,524(1-3):37-42
In our previous papers [e.g. Sato et al., J. Biol. Chem. 273 (1998) 21455-21462], we have shown that prodigiosins can uncouple various H(+)-ATPases through their H(+)/Cl(-) symport activity. BE-18591 is an enamine of 4-methoxy-2,2'-bipyrrole-5-carboxyaldehyde (tambjamine group antibiotics) which resembles the prodigiosins. We found that BE-18591 was a new group of antibiotics that uncouples various H(+)-ATPases: it inhibited proton pump activities with IC(50)s of about 1-2 nM (about 20 pmol/mg protein) for submitochondrial particles as well as gastric vesicles and of 230 nM (about 230 pmol/mg protein) for lysosomes, but it had little effect on their ATP hydrolyses (up to 10 microM), a property of H(+)/Cl(-) symport activity. At low concentrations (<1 microM), BE-18591 inhibited immunoproliferation, the IC(50) of lipopolysaccharide-stimulated mouse splenocytes was 38 nM, that of Concanavalin A-stimulated cells was 230 nM. Gastritis of rabbits was also inhibited. At higher concentrations (>1 microM), BE-18591 induced neurite outgrowth (15% induction in 48 h at 4 microM), inhibited bone resorption (approximately 35% in 48 h at 10 microM) and caused cell death (approximately 30% in 48 h at 4 microM) but with little apoptosis.  相似文献   

20.
Cetirizine, terfenadine, loratadine, astemizole and mizolastine were compared for their ability to inhibit marker activities for CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP3A4 and for some glucuronidation isoenzymes in human liver microsomes. The most pronounced effects were observed with terfenadine, astemizole and loratadine which inhibited CYP3A4-mediated testosterone 6beta-hydroxylation (IC50 of 23, 21 and 32 microM, respectively) and CYP2D6-mediated dextromethorphan O-demethylation (IC50 of 18, 36 and 15 microM, respectively). In addition, loratadine markedly inhibited the CYP2C19 marker activity, (S)-mephenytoin 4-hydroxylation (Ki of 0.17 microM). Furthermore, loratadine activated the CYP2C9-catalyzed tolbutamide hydroxylation (ca. 3-fold increase at 30 microM) and inhibited some glucuronidation enzymes. Mizolastine appeared to be a relatively weak and unspecific inhibitor of CYP2E1, CYP2C9, CYP2D6 and CYP3A4 (IC50Ss in the 100 micromolar range). Cetirizine demonstrated no effect on the investigated activities. A comparison of the inhibitory potencies of cetirizine, terfenadine, loratidine, astemizole and mizolastine with their corresponding plasma concentrations in humans suggests that these antihistamines are not likely to interfere with the metabolic clearance of coadministered drugs, with the exception of loratidine, which appears to inhibit CYP2C19 with sufficient potency to warrant additional investigation.  相似文献   

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