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1.
Allergy, Asthma & Immunology Research ; : 457-460, 2016.
Artículo en Inglés | WPRIM | ID: wpr-90239

RESUMEN

Chronic spontaneous urticaria (CSU) is a complex idiopathic disease of the skin with various cellular infiltrations. Although mast cells are key effector cells in the pathogenesis of CSU, CD4+ T helper 2 cells also have particular roles in the development and maintenance of CSU. Periostin is known as a downstream molecule of interleukin (IL)-4 and IL-13, key cytokines of type 2 immune responses. In this study, we examined periostin and IL-13 levels in the sera of patients with CSU (n=84) and healthy normal controls (NCs, n=43). Periostin levels were significantly lower in the CSU group than in NCs (71.4±21.8 vs 85.1±22.4 ng/mL, P=0.04). Periostin levels were also lower in the severe CSU group than those in mild CSU (59.7±18.0 vs 73.4±22.0 ng/mL, P=0.04). However, IL-13 levels were significantly higher in patients with CSU than in NCs (508.5±51.2 vs 200.7±13.3 pg/mL, P=0.001). In conclusion, periostin and IL-13 may be independently related to the pathogenesis of CSU.


Asunto(s)
Humanos , Citocinas , Interleucina-13 , Interleucinas , Mastocitos , Piel , Urticaria
2.
Experimental & Molecular Medicine ; : 277-287, 2009.
Artículo en Inglés | WPRIM | ID: wpr-49339

RESUMEN

Matrix metalloproteinase-9 (MMP-9) may play an important role in emphysematous change in chronic obstructive pulmonary disease (COPD), one of the leading causes of mortality and morbidity worldwide. We previously reported that simvastatin, an inhibitor of HMG-CoA reductase, attenuates emphysematous change and MMP-9 induction in the lungs of rats exposed to cigarette smoke. However, it remained uncertain how cigarette smoke induced MMP-9 and how simvastatin inhibited cigarette smoke-induced MMP-9 expression in alveolar macrophages (AMs), a major source of MMP-9 in the lungs of COPD patients. Presently, we examined the related signaling for MMP-9 induction and the inhibitory mechanism of simvastatin on MMP-9 induction in AMs exposed to cigarette smoke extract (CSE). In isolated rat AMs, CSE induced MMP-9 expression and phosphorylation of ERK and Akt. A chemical inhibitor of MEK1/2 or PI3K reduced phosphorylation of ERK or Akt, respectively, and also inhibited CSE-mediated MMP-9 induction. Simvastatin reduced CSE-mediated MMP-9 induction, and simvastatin-mediated inhibition was reversed by farnesyl pyrophosphate (FPP) or geranylgeranyl pyrophosphate (GGPP). Similar to simvastatin, inhibition of FPP transferase or GGPP transferase suppressed CSE-mediated MMP-9 induction. Simvastatin attenuated CSE-mediated activation of RAS and phosphorylation of ERK, Akt, p65, IkappaB, and nuclear AP-1 or NF-kappaB activity. Taken together, these results suggest that simvastatin may inhibit CSE-mediated MMP-9 induction, primarily by blocking prenylation of RAS in the signaling pathways, in which Raf-MEK-ERK, PI3K/Akt, AP-1, and IkappaB-NF-kappaB are involved.


Asunto(s)
Animales , Ratas , Fosfatidilinositol 3-Quinasa/metabolismo , Transferasas Alquil y Aril/metabolismo , Anticolesterolemiantes/farmacología , Células Cultivadas , Inhibidores Enzimáticos/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Quinasa I-kappa B/antagonistas & inhibidores , Macrófagos Alveolares/citología , Metaloproteinasa 9 de la Matriz/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Fosfatos de Poliisoprenilo/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Sesquiterpenos/metabolismo , Transducción de Señal/fisiología , Simvastatina/farmacología , Humo/efectos adversos , Nicotiana/efectos adversos
3.
Journal of Asthma, Allergy and Clinical Immunology ; : 1187-1200, 2001.
Artículo en Inglés | WPRIM | ID: wpr-220254

RESUMEN

BACKGROUND: It has been reported that Korean Red Ginseng saponins are effective in increasing the synthesis of serum proteins, in cellular proliferation, in producing antibody against sheep red blood cells, and in various cancer. However, there have been no reports yet on the immunomodulating activity of this allergic disease. OBJECTIVE: This study was conducted to find the immunomodulating activity of a single highly purified ginsenoside, Rb1, by using ovalbumin(OVA) as the antigen. METHOD: BALB/c mice were immunized subcutaneously with OVA containing the alum or ginsenoside, Rb1, twice per 2wk interval. Antigen-specific antibodies and IgG subclasses were determined from serum recovered by cardiac puncture 2 wk after the second immunization by using ELISA method. Antigen-specific cellular proliferation and cytokines were quantified from splenotes obtained from spleens immunized. Cytokine level in cell culture supernatants were determined by ELISA method. NK cell cytotoxicity was generated by co-culture of splenic mononuclear cells against YAC-1 cells as target cells. Hemolytic activity of Rb1 was determined by an in vitro assay using sheep red blood cells. RESULTS: BALB/c mice immunized with OVA plus Rb1 produced significantly higher titers of antibodies than mice immunized with alum-adsorbed antigen. Rb1 remarkably increased titers in IgG2a and IgG2b subclasses. Antigen-specific proliferative response was more significantly increased with the use of Rb1 than with alum-adsorbed antigen. Rb1 reduced IL-4 production, increased IL-10 production more than alum-adsorbed OVA, but did not affect the IFN-gamma production. High concentration of Rb1 increased the splenic mononuclear cells that were capable of killing YAC-1 cells. Rb1 did not stimulate the production of reaginic antibody (IgE) but alum was able to induce it. Rb1 did not show any hemolytic activity up to 500microgram/ml. CONCLUSION: The data suggest that the highly purified ginsenoside extracted from Korean Red Ginseng Radix, Rb1, can actively influence the switch of Igs produced by OVA. The data also suggest that Rb1 may be an immunosurveillant in NK cytotoxic activity.


Asunto(s)
Animales , Ratones , Anticuerpos , Proteínas Sanguíneas , Técnicas de Cultivo de Célula , Proliferación Celular , Técnicas de Cocultivo , Citocinas , Ensayo de Inmunoadsorción Enzimática , Eritrocitos , Homicidio , Inmunización , Inmunoglobulina G , Interleucina-10 , Interleucina-4 , Células Asesinas Naturales , Ovalbúmina , Óvulo , Panax , Punciones , Saponinas , Ovinos , Bazo
4.
Korean Journal of Dermatology ; : 43-49, 2001.
Artículo en Coreano | WPRIM | ID: wpr-176273

RESUMEN

The pathogenesis of chronic idiopathic urticaria is not completely understood, but mast cell degranulation and histamine release are thought to be of central importance. It is now established that circulating autoantibodies against the high-affinity IgE receptor(Fc(epsilon)RIalpha) can be found approximately one third of patients with chronic idiopathic urticaria. These autoantibodies can be detected by in vivo autologous serum skin test and by in vitro basophil and mast cell histamine release assays as functional tests, and also can be confirmed by in vitro enzyme-linked immunosorbent assay to Fc(epsilon)RIalpha and Western blot analysis. Our purpose was to determine the proportion of patients with positive autologous serum skin test and anti-Fc(epsilon)RIalpha antibody in chronic idiopathic urticaria and whether there are differences between patients with and those without autoantibodies in the clinical features. RESULTS ARE AS FOLLOWS: 1. Positive result to autologous serum skin test was 58.5% in 41 patients of chronic idiopathic urticaria. There was no significant difference of clinical features and laboratory tests between patients with positive skin test and those with negative results. 2. By enzyme-linked immunosorbent assay, anti-Fc(epsilon)RIalpha antibody was detected in sera from 34% of patients with chronic idiopathic urticaria. 3. In sera from 33% of patients with positive skin test and 35% of those with negative result, we could demonstrate anti-Fc(epsilon)RIalpha antibody by enzyme-linked immunosorbent assay. 4. There was no differences of clinical features and laboratory tests between the patients with autoantibodies to Fc(epsilon)RIalpha and those without, except female predominance and longer urticaria history in those with autoantibodies.


Asunto(s)
Femenino , Humanos , Autoanticuerpos , Basófilos , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Liberación de Histamina , Inmunoglobulina E , Mastocitos , Pruebas Cutáneas , Urticaria
5.
Yonsei Medical Journal ; : 91-105, 2001.
Artículo en Inglés | WPRIM | ID: wpr-15147

RESUMEN

For those with allergy, vaccination with a specific allergen has often been used as a major therapeutic measure. However, the universal application of this technique in clinics have been restricted due to its low success rates and the risk of active systemic anaphylactic shock (ASAS). In this regard, we constructed a fusion protein (OVA-DT), ovalbumin (OVA) fused with diphtheria toxin protein (DT), which may exert a specific cytotoxicity to cells bearing OVA-specific IgE. Its therapeutic effect was evaluated in mice (BALB/c) sensitized with OVA (Os-mice). OVA challenges to the OVA-sensitized mice (Os-mice) caused ASAS to death within 30 min, but OVA-DT treatment afforded mice complete protection. When OVA-DT was treated to the Os-mice, none showed the signs of ASAS when re-challenged 48 h after the treatment. OVA-DT itself was not found to be toxic or allergenic in normal mice. The effect of OVA-DT on the biological functions of mast cells was also studied. Binding of OVA-DT to OVA-specific IgE bearing mast cells and the inhibition of histamine release from these cells were observed. In addition, OVA-DT treatment inhibited the proliferation of OVA-specific B cells in mice. In Os-mice treated with OVA-DT, levels of anti-OVA IgG2a in serum and the production of IFN-gamma by splenic lymphocytes were found to increase, but the production of IL-4 by these cells decreased. Re-direction of cytokine profiles from OVA-specific Th2 to OVA-specific Thl is suggested. These results indicate that OVA-DT can protect Os-mice from ASAS due to OVA challenge, because it inactivates OVA-specific IgE-expressing cells, including mast cells and B cells.


Asunto(s)
Femenino , Ratones , Anafilaxia , Animales , Linfocitos B/inmunología , Liberación de Histamina/efectos de los fármacos , Inmunoglobulina E/metabolismo , Interferón gamma/biosíntesis , Interleucina-4/biosíntesis , Activación de Linfocitos/efectos de los fármacos , Mastocitos/metabolismo , Ratones Endogámicos BALB C , Ovalbúmina/inmunología , Proteínas Recombinantes de Fusión/uso terapéutico
6.
The Korean Journal of Physiology and Pharmacology ; : 251-260, 1998.
Artículo en Inglés | WPRIM | ID: wpr-727535

RESUMEN

Cromakalim (BRL 34915), known as an airway smooth muscle relaxant, inhibited the releases of mediators in the antigen-induced mast cell activation. It has been suggested that cromakalim, in part, inhibited mediator releases by inhibiting the initial increase of 1,2-diacylglycerol (DAG) produced by the activation of the other phospholipase system which is different from phosphatidylcholine-phospholipase D pathway. The aim of this study is to further examine the inhibitory mechanism of cromakalim on the mediator release in the mast cell activation. Guinea pig lung mast cells were purified by using enzyme digestion and percoll density gradient. In purified mast cells prelabeled with (3H)PIP2, phospholipase C (PLC) activity was assessed by the production of (3H)insitol phosphates. Protein kinase C (PKC) activity was assessed by measuring the protein phosphorylated from mast cells prelabeled with (gamma-32P)ATP, and Phospholipase A2 (PLA2) activity by measuring the lyso-phosphatidylcholine produced from mast cell prelabeled with 1-palmitoyl-2-arachidonyl phosphatidyl-(14C)choline. Histamine was assayed by fluorometric analyzer, and leukotrienes by radioimmunoassay. The PLC activity was increased by activation of the passively sensitized mast cells. This increased PLC activity was decreased by cromakalim pretreatment. The PKC activity increased by the activation of the passively sensitized mast cells was decreased by calphostin C, staurosporine and cromakalim, respectively. The PLA2 activity was increased in the activated mast cells. The pretreatment of cromakalim did not significantly decrease PLA2 activity. These data show that cromakalim inhibits histamine release by continuously inhibiting signal transduction processes which is mediated via PLC pathway during mast cell activation, but that cromakalim does not affect PLA2 activity related to leukotriene release.


Asunto(s)
Animales , Reacciones Antígeno-Anticuerpo , Cromakalim , Digestión , Cobayas , Guinea , Histamina , Liberación de Histamina , Leucotrienos , Pulmón , Mastocitos , Membranas , Músculo Liso , Fosfatos , Fosfolipasas , Fosfolipasas A2 , Proteína Quinasa C , Radioinmunoensayo , Transducción de Señal , Estaurosporina , Fosfolipasas de Tipo C
7.
The Korean Journal of Physiology and Pharmacology ; : 119-131, 1998.
Artículo en Inglés | WPRIM | ID: wpr-728152

RESUMEN

It has been reported that the glycoprotein extracted from Aloe has strong anti-inflammatory response. However, there has been no research report yet about the effect of Aloe on allergic hypersensitivity reactivity. By using guinea pig lung mast cells, this study aimed to examine the effects of Aloe glycoprotein (NY945) on the mediator releases caused by mast cell activation, and also aimed to assess the effects of NY945 on the mechanism of mediator releases in the mast cell activation. We partially purified mast cell from guinea pig lung tissues by using the enzyme digestion, the rough and the discontinuous density percoll gradient method. Mast cells were sensitized with IgG, (anti-OA) and challenged with ovalbumin. Histamine was assayed by fluorometric analyzer, leukotrienes by radioimmunoassay. The phospholipase D activity was assessed by the production of labeled phosphatidylalcohol. The amount of mass 1, 2-diacylglycerol (DAG) was measured by the (3H)-DAG produced when prelabeled with (3H)myristic acid. The phospholipid methylation was assessed by measuring the incorporation of the (3H)methyl moiety into phospholipids of cellular membranes. Pretreatment of NY945 (10 microgram) significantly decreased histamine and leukotrienes releases during mast cell activation. The decrease of histamine release was stronger than that of leukotriene during mast cell activation. The phospholipase D activity increased by the mast cell activation was decreased by the dose-dependent manner in the pretreatment of NY945. The amount of DAG produced by PLC activity was decreased by NY945 pretreatment. The amount of -mass 1, 2-diacylglycerol produced by activation of mast cells was decreased in the pretreatment of NY945. NY945 pretreatment strongly inhibited the incorporation of the (3H)-methyl moiety into phospholipids. The data suggest that NY945 purified from Aloe inhibits in part an increase of 1, 2-diacylglycerol which is produced by activating mast cells with antigen-antibody reactions, which is mediated via phosphatidylcholine-phospholipase D and phosphatidylinositol-phospholipase C systems, and then followed by the inhibition of histamine release. Furthermore, NY945 reduces the production of phosphatidylcholine by inhibiting the methyltransferase I and II, which decreases the conversion of phosphatidylcholine into arachidonic acid and inhibits the production of leukotrienes.


Asunto(s)
Animales , Aloe , Complejo Antígeno-Anticuerpo , Reacciones Antígeno-Anticuerpo , Ácido Araquidónico , Digestión , Glicoproteínas , Cobayas , Guinea , Histamina , Liberación de Histamina , Hipersensibilidad , Inmunoglobulina G , Leucotrienos , Pulmón , Mastocitos , Membranas , Metilación , Ovalbúmina , Fosfatidilcolinas , Fosfolipasa D , Fosfolípidos , Radioinmunoensayo , Informe de Investigación
8.
The Korean Journal of Physiology and Pharmacology ; : 825-830, 1997.
Artículo en Inglés | WPRIM | ID: wpr-728167

RESUMEN

Leukotrienes (LTs) are known to act as a mediator provoking tissue response in inflammation. This finding implicates that LTs also play important roles in the pathogenesis of H. pylori-induced gastritis and gastric ulceration. Rebamipide is being currently used as a therapeutics for gastritis and peptic ulcer, but their mechanisms of action have not been known clearly yet. One possibility is that their therapeutic effects are ascribed to interfering with the H. pylori-induced release of LTs from neutrophils and gastric mucosal cells. In the present study, this possibility was tested using LTB4 as the test material in human neutrophils and Kato III cells(gastric adenoma cells as a substitute for gastric mucosal cells). The release of LTB4 from both neutrophils and Kato III cells was time and H. pylori-dose dependent. The maximum release of LTB4 was induced by neutrophils and Kato III cells when these cells incubated with H. pylori 4.8 X 108 cells/ml for 30 min. But in the presence of rebamipide the release of LTB4 from these cells was suppressed in dose dependent manners. The release was completely suppressed at 1.0 mM of rebamipide in neutrophils and 2.0 mM of this drug in Kato III cells, respectively. We also obtained the results that the release of LTB4 was induced by A23187 (Ca2+ ionophore) and the A23187-induced release was also inhibited by rebamipide. It seems that the mechanism of action of rebamipide is through its interaction with the level of intracellular Ca2+. In view of the roles of LTB4 in inflammatory reaction and the roles of H. pylori in gastritis and peptic ulcer, the effects of this drug observed in this study may contribute to their therapeutic action in these gastric disorders.


Asunto(s)
Humanos , Adenoma , Calcimicina , Gastritis , Helicobacter pylori , Helicobacter , Inflamación , Leucotrieno B4 , Leucotrienos , Neutrófilos , Úlcera Péptica , Úlcera Gástrica
9.
The Korean Journal of Physiology and Pharmacology ; : 445-456, 1997.
Artículo en Inglés | WPRIM | ID: wpr-728088

RESUMEN

We previously reported that some components of ginsenosides decreased mediator releases evoked by the activation of mast cells with specific antigen-antibody reactions. This study aimed to assess the effects of ginsenosides (Rb2, Re) on the mechanism of histamine release in the mast cell activation. We partially purified guinea pig lung mast cells by using enzyme digestion, the rough and the discontinuous percoll density gradient method. Mast cells were sensitized with IgG1 and challenged with ovalbumin (OA). Histamine was assayed by fluorometric analyzer, leukotrienes by radioimmunoassay. Phospholipase D (PLD) activity was assessed more directly by the production of (3H)phosphatidylbutanol (PBut) which was produced by PLD-mediated transphosphatidylation in the presence of butanol. The amount of 1,2-diacylglycerol (DAG) were measured by the (3H)DAG labeled with (3H)palmitic acid or (3H)myristic acid. Pretreatment of Rb2 (300 microgram) significantly decreased histamine release by 60%, but Re (300 gg) increased histamine release by 34%. Leukotrienes release in Rb2 was decreased by 40%, Re was not affected in the leukotrienes release during mast cell activations. An increasing PLD activity during mast cell activation was decreased by the dose-dependent manner in the pretreatment of Rb2, but Re pretreatment facilitated the increased PLD activity during mast cell activation. The amount of DAG produced by phospholipase C (PLC) activity was decreased by Rb2 pretreatment, but Re pretreatment was not affected. The amount of mass DAG was decreased by Rb2 and Re pretreatment during mast cell activation. The data suggest that Rb2 purified from Korean Red Ginseng Radix inhibits the DAG which is produced by the activation of mast cells with antigen-antibody reactions via both phosphatidylinositide-PLC and phosphatidylcholine-PLD systems, and then followed by the inhibition of histamine release. However, Re increases histamine release by stimulation of DAG production, which is mediated by phosphatidylcholine-PLD system rather than by phosphatidylinositide-PLC system, but inhibits the mass DAG production. Thus, it could be inferred that other mechanisms play a role in the increase of histamine release during mast cell activation.


Asunto(s)
Animales , Reacciones Antígeno-Anticuerpo , Digestión , Ginsenósidos , Cobayas , Guinea , Liberación de Histamina , Histamina , Inmunoglobulina G , Leucotrienos , Pulmón , Mastocitos , Ovalbúmina , Panax , Fosfolipasa D , Radioinmunoensayo , Fosfolipasas de Tipo C
10.
Yonsei Medical Journal ; : 230-235, 1996.
Artículo en Inglés | WPRIM | ID: wpr-176627

RESUMEN

Heat contact urticaria is very rare and it is characterized by the development of wheal limited to the areas of heat contact. We report a case of heat contact urticaria in a 65-year-old women. The wheal was induced by hot bathing, washing in hot water or leaning on hot radiators. Symptoms started within 5 minutes of exposure and lasted 30 to 60 minutes. She had no systemic symptoms. The clinical diagnosis of localized heat urticaria was confirmed by experimental induction of localized wheals. Our investigation showed that the threshold temperature needed for induction of the heat urticaria was 39 degrees C. We tried to investigate the plasma levels of prostaglandin D2 and blood histamine before and after heat challenge. The patient showed marked improvement after a combination treatment of desensitizing by repeated exposure to heat and indomethacine.


Asunto(s)
Anciano , Femenino , Humanos , Calor/efectos adversos , Prostaglandina D2/sangre , Urticaria/etiología
11.
Yonsei Medical Journal ; : 325-338, 1996.
Artículo en Inglés | WPRIM | ID: wpr-135747

RESUMEN

The inhibitory effect of cromakalim on the mediator release from mast cells caused by antigenantibody reactions was in controversy with the specific antigen used. However, it has recently been observed that cromakalim inhibits the release of mediators from superfused tracheal and parenchymal strips or lung mast cells after passive sensitization with the IgG1 antibody. An attempt, therefore, was made to determine the inhibitory mechanisms of cromakalim on the release of mediators such as histamine and leukotriene released by the activation of enzymes during mast cell activation. Guinea pig lung mast cells were purified through enzyme digestion, rough percoll and continuous percoll density gradients. The purified mast cells were prelabeled with [3H]palmitic acid. PLD activity was assessed more directly by the production of labeled phosphatidylethanol by PLD-mediated transphosphatidylation in the presence of ethanol. In the cells labelled with [3H]myristic acid, [3H] DAG production was measured. The methyltransferase activity was assessed by measuring the incorporation of [3H]methyl moiety into phospholipids in sensitized mast cells labelled with L-[3H] methylmethionine. cAMP level was measured by radioimmunoassay. Cromakalim resulted in a decrease in the amount of histamine and leukotrienes releases by 30% in the ovalumin-induced mast cell. Cromakalim had little effect on phospholipase D activity enhanced by the activated mast cell. Cromakalim inhibited the initial increase of diacylglycerol production during mast cell activations. Cromakalim inhibited the phospholipid methylation increased in the activated mast cell. These results show that cromakalim decreases histamine release by inhibiting the initial increase of 1,2-diacylglycerol during the mast cell activation, which is mediated via the phosphatidylinositide-phospholipase C system rather than the phosphatidylcholine-phospholipase D system. Furthermore, cromakalim reduces phosphatidylcholine production by inhibiting the methyltransferase, which decreases the conversion of phosphatidylcholine into arachidonic acid and inhibits the production of leukotrienes.


Asunto(s)
Femenino , Adenilil Ciclasas/metabolismo , Animales , Reacciones Antígeno-Anticuerpo , Benzopiranos/farmacología , Cromakalim , Diglicéridos/biosíntesis , Cobayas , Liberación de Histamina/efectos de los fármacos , Leucotrienos/metabolismo , Pulmón/efectos de los fármacos , Mastocitos/efectos de los fármacos , Metilación , Fosfolipasa D/metabolismo , Fosfolípidos/metabolismo , Canales de Potasio/efectos de los fármacos , Pirroles/farmacología
12.
Yonsei Medical Journal ; : 325-338, 1996.
Artículo en Inglés | WPRIM | ID: wpr-135742

RESUMEN

The inhibitory effect of cromakalim on the mediator release from mast cells caused by antigenantibody reactions was in controversy with the specific antigen used. However, it has recently been observed that cromakalim inhibits the release of mediators from superfused tracheal and parenchymal strips or lung mast cells after passive sensitization with the IgG1 antibody. An attempt, therefore, was made to determine the inhibitory mechanisms of cromakalim on the release of mediators such as histamine and leukotriene released by the activation of enzymes during mast cell activation. Guinea pig lung mast cells were purified through enzyme digestion, rough percoll and continuous percoll density gradients. The purified mast cells were prelabeled with [3H]palmitic acid. PLD activity was assessed more directly by the production of labeled phosphatidylethanol by PLD-mediated transphosphatidylation in the presence of ethanol. In the cells labelled with [3H]myristic acid, [3H] DAG production was measured. The methyltransferase activity was assessed by measuring the incorporation of [3H]methyl moiety into phospholipids in sensitized mast cells labelled with L-[3H] methylmethionine. cAMP level was measured by radioimmunoassay. Cromakalim resulted in a decrease in the amount of histamine and leukotrienes releases by 30% in the ovalumin-induced mast cell. Cromakalim had little effect on phospholipase D activity enhanced by the activated mast cell. Cromakalim inhibited the initial increase of diacylglycerol production during mast cell activations. Cromakalim inhibited the phospholipid methylation increased in the activated mast cell. These results show that cromakalim decreases histamine release by inhibiting the initial increase of 1,2-diacylglycerol during the mast cell activation, which is mediated via the phosphatidylinositide-phospholipase C system rather than the phosphatidylcholine-phospholipase D system. Furthermore, cromakalim reduces phosphatidylcholine production by inhibiting the methyltransferase, which decreases the conversion of phosphatidylcholine into arachidonic acid and inhibits the production of leukotrienes.


Asunto(s)
Femenino , Adenilil Ciclasas/metabolismo , Animales , Reacciones Antígeno-Anticuerpo , Benzopiranos/farmacología , Cromakalim , Diglicéridos/biosíntesis , Cobayas , Liberación de Histamina/efectos de los fármacos , Leucotrienos/metabolismo , Pulmón/efectos de los fármacos , Mastocitos/efectos de los fármacos , Metilación , Fosfolipasa D/metabolismo , Fosfolípidos/metabolismo , Canales de Potasio/efectos de los fármacos , Pirroles/farmacología
13.
Yonsei Medical Journal ; : 161-174, 1995.
Artículo en Inglés | WPRIM | ID: wpr-122035

RESUMEN

In the present work, we have examined the effect of PAF, removal of epithelium, the mechanism of desensitization, and the substances that increases the level of intracellular c-AMP on the differences of mediator release from superfused tracheal strips after passive sensitization with IgG1 versus IgE Ab. In the passive sensitized tracheal tissues, the effect of PAF and the mechanism of desensitization have been examined by PAF antagonist, CV 3988 and DFP, respectively. The epithelium was stripped from one-half of each trachea by mechanical means. Both superfused tracheal tissues were challenged with Ox-Ag. Inhibitors of mediator release were added into a superfused buffer. Hist released was determined by spectrophotofluorometer, and LT by radioimmunoassay. PAF known to mediate the allergic reaction was not released by Ag after both Ab sensitization. Epithelium removal resulted in similar contraction, Hist and LT release after IgG1 Ab activation, but in the IgE Ab activation, epithelium removal resulted in smaller contraction and Hist release. In the L-cysteine and indomethacin pretreatment after two Ab sensitization, epithelium removal decreased the release of Hist and LT. The compound 48/80 pre-challenge and epithelium removal resulted in the increase of Hist release, but in the decrease of LT release after IgG1 or IgE sensitization. The Amount of LT released by Ag after compound 48/80 pre-challenge increased in the absence or presence of epithelium after both Ab sensitization. Mediator release from tissues sensitized with both Abs was not changed by DFP. The responses of inhibitors to prevent the mediator release were more effective on the IgE Ab than on the IgG1 Ab sensitization. These studies suggest that the tracheal epithelium can act to inhibit immune- and non-immune-induced airway responses. Non-immunological responses may in part reflect the role of epithelium as a diffusion barrier and modulator of mediator release. These data also suggest that immunological responses are related to the localization and functional heterogeneity of tissue mast cells.


Asunto(s)
Femenino , Animales , Epitelio/inmunología , Cobayas , Liberación de Histamina , Inmunización , Inmunoglobulina E/inmunología , Inmunoglobulina G/inmunología , Leucotrienos/metabolismo , Mastocitos/inmunología , Tráquea/inmunología
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