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1.
M. De la Fuente A. Hernanz M. E. Collazos C. Barriga E. Ortega 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1995,165(4):315-319
The relationship of physical activity and aging, two processes with a high production of oxygen-free radicals to the ascorbate and superoxide anion (O
2
-
) contents of peritoneal macrophages was studied in two animal species: guinea-pig (in which ascorbic acid is a vitamin) and mouse (in which ascorbic acid is not a vitamin). The effects of exhaustive exercise were examined in young and old animals. The results show that macrophages from old animals have a lower ascorbate content than those from young ones, whereas with exercise the ascorbate content increased in both old and young animals. This increase was higher in young than in old animals, and more evident in mice than in guinea-pigs. Aging also resulted in an increase in the O
2
-
levels of macrophages. With exercise these levels decreased in young mice but increased in young guinea-pigs. In old animals the exhaustive exercise did not change the O
2
-
levels. The results suggest in general a lack of correlation between the intracellular ascorbate and O
2
-
levels in relation to both physical exercise and aging.Abbreviations
PBS
phosphate buffered saline
-
NBT
nitroblue tetrazolium
-
PEC
peritoneal exudate cells
-
PMN
polymorphonuclear 相似文献
2.
The purpose of this study was to elucidate the role of NO and O-2 on enzymatic components of cyclooxygenase (COX) pathway in peritoneal macrophages. Activation of murine peritoneal macrophages by lipopolysaccharides (LPS) resulted in time-dependent production of nitric oxide (NO) and prostaglandin E2 (PGE2). This stimulation was also accompanied by the production of other reactive oxygen species such as superoxide (O-2), and by increased expression of COX-2. Our results provide evidence that O-2 may be involved in the pathways that result in arachidonate release and PGE2 formation by COX-2 in murine peritoneal macrophages stimulated by LPS. However, we were not able to demonstrate that NO participates in the regulation of PG production under our experimental conditions. 相似文献
3.
Decreased superoxide anion radical production by rat alveolar macrophages following inhalation of ozone or nitrogen dioxide 总被引:2,自引:0,他引:2
exposure of rats to ozone or nitrogen dioxide results in a dose-dependent decrease in superoxide anion radical production (O2?·) by alveolar macrophages isolated from the exposed animals. When alveolar macrophages from ozone-exposed animals were stimulated with phorbol myristate acetate (PMA, a non-phagocytic stimulus of O2?· production) the decrease in O2?· production ranged from 85.9% of control at 3.2 ppm-hrs ozone to 7% of control at 10.5 ppm-hrs. In a similar fashion, O2?· production by PMA-stimulated macrophages from NO2-exposed rates ranged from 78% of control at 18.3 ppm-hrs NO2 down to 14.5% of control at 51 ppm-hrs. Since the viability of the alveolar macrophages obtained from ozone or nitrogen dioxide-exposed animals was 88% or better in all cases as judged by both Trypan blue exclusion and lactate dehydrogenase release, the decreased ability of these cells to produce superoxide anion radical cannot be attributed to a pollutant effect on cell viability. This diminution in superoxide anion radical production by alveolar macrophages from the pollutant-exposed animals might account, in part, for the ability of these 2 air pollutants to potentiate bacterial infections in laboratory animals. 相似文献
4.
ANIL K. BHUNIA DWIJEN SARKAR PIJUSH K. DAS 《The Journal of eukaryotic microbiology》1996,43(5):373-379
We investigated activation signaling events in bone marrow-derived macrophages after infection with Leishmania donovani, an intracellular parasite of macrophages. Leishmania donovani infection caused a general suppression of activation parameters like O2- and NO production. However, conditions which allow parasite attachment and prevent entry resulted in triggering of O2- and NO production and stimulation of O2 consumption. Optimal NO and O2- production occurred when bone marrow-derived macrophages and Leishmania ratio was 1:100. The activation signal for O2- production was initiated 15 min after parasite attachment, whereas augmentation of NO production started 6 h after attachment. Activation of O2- and NO generation by L. donovani attachment was inhibited by staurosporine as well as by prolonged treatment of phorbol myristate acetate suggesting a protein kinase C-dependent mechanism. Translocation studies showed that protein kinase C activity in cell membrane fraction rapidly and transiently increased following parasite attachment. No such protein kinase C translocation event occurred in L. donovani infected bone marrow-derived macrophages. Phorbol myristate acetate was found to stimulate membrane translocation of protein kinase C in parasite attached cells whereas it was impaired in infected cells. However, both attachment and infection induced a similar shift of phorbol receptors from cytosolic to membrane fraction indicating that in infected cells the translocation of protein kinase C protein was not impaired but the activity of the membrane associated enzyme was somehow inhibited. These results suggest that although internalization of intracellular parasites like L. donovani caused inhibition of nitrite and superoxide release, mere attachment on macrophage surface resulted in an activation of protein kinase C-mediated downstream oxidative events. 相似文献
5.
Tetsu Sasaoki Shigeki Arii Kazunobu Monden Shigeyuki Itai Yukito Adachi Naomi Funaki Hiroaki Higashituji Takayoshi Tobe 《Cancer immunology, immunotherapy : CII》1992,35(2):75-82
Summary The effect of biological response modifiers, such as interleukin-2 (IL-2) and streptococcal preparation OK432, on the functions of hepatic macrophages was investigated. The macrophages, even with no exogenous stimulation, produced superoxide anion (O
2
-
) and tumor necrosis factor (TNF), displayed cytotoxicity against K562 cells and cytostasis against P815 cells and expressed immune-region-associated antigen (Ia). IL-2 administered in vitro or in vivo enhanced O
2
-
production by hepatic macrophages and the intravenous injection of OK432 also enhanced O
2
-
production. Furthermore, IL-2 added to the culture medium of hepatic macrophages isolated from OK432-injected rats augmented O
2
-
production even more. The TNF production and Ia expression of the macrophages were also increased by the intravenous injection of OK432. As with O
2
-
production, the cytotoxicity of the cells was enhanced by OK432 injection or by IL-2 added to the culture medium and the combination of OK432 and IL-2 augmented their cytotoxicity even more. Thus, the present study suggested that IL-2 and OK432 induce the augmentation of the antitumor activity of hepatic macrophages, partly as a result of the increase in production of O
2
-
and TNF and Ia expression. 相似文献
6.
Sergio D. Catz Maria C. Carreras Juan J. Poderoso 《Free radical biology & medicine》1995,19(6):741-748
Nitric oxide synthase (NOS) inhibitors have been reported to modulate luminol-dependent chemiluminescence (CL) in rat macrophages, whereas the potent oxidant peroxynitrite (ONOO-) was shown to react with luminol to yield CL in a cellfree system. We evaluated the role of the
-arginine/NOS pathway in luminol CL by phorbol ester-activated human polymorpho-nuclear (PMN) leukocytes using the NOS inhibitors NG-monomethyl-
-arginine (
-NMMA) and N-iminoethyl-
-omithine (
-NIO). Nitric oxide (·NO) release was determined by oxidation of oxymyoglobin. In addition, the effect of NOS inhibitors on superoxide anion O2-) production was measured. Luminol CL was notably diminished by
-NMMA in a dose-dependent manner. Superoxide dismutase (SOD) also decreased luminol CL and
-NMMA potentiated light emission decrease produced by SOD. Nitric oxide and O2·- production was significantly decreased by
-NMMA; moreover, luminol-dependent CL but not O2·- production was attenuated by
-NIO. These data suggest that products of catalytic activity of both ·NO synthase and NADPH oxidase are required to elicit maximal luminol CL in this system. These studies demonstrate that the NOS synthase pathway is involved in luminol CL by human PMN, and they suggest that ONOO would be an unrecognized mediator in this phenomenon. 相似文献
7.
SummaryOxygen (O2)-dependent and O2-independent antimicrobial mechanisms are used by alveolar macrophages (AM) to maintain lung sterility, but these mechanisms are underdeveloped in neonatal AM. Nitric oxide (NO.), a more recently described antimicrobial and immunomodulating molecule, has not been studied in neonatal AM. Lavaged AM from 3-day-old, 10-day-old, maternal and adult rats were treated with or without lipopolysaccharide (LPS) and/or interferon-γ (IFN-γ) and NO. synthase activity was measured as its L-arginine metabolites: NO2?, NO3?, and citrulline. Superoxide anion (O2.-) production by suspended macrophages, initiated by either opsonized zymosan or phorbol, was used as a marker of O2-dependent antimicrobial activity. Lysozyme content of AM was measured as a component of O2-independent antimicrobial activity. Unstimulated 3-day-old macrophages generated >10-fold more NO2? + NO3? than did 10-day-old, maternal or adult AM. Twenty hours after LPS and IFN-γ stimulation, 3-day-old AM produced > 2 times more NO2? and NO3? than did the more mature macrophages. Basal and stimulated O2.- release was similar among 3-day-old, 10-day-old and adult AM, while lysozyme concentrations were > 4-fold higher in adult macrophages compared to AM from 3-day-old pups. Rather than having a role in NO.-dependent antimicrobial activity, we propose that newborn AM have amplified NO. production to modulate their own differentiation and replication after birth. The age-dependent differences in NO. synthase expression by AM may lend insight into the regulation of this important enzyme. 相似文献
8.
Y Keisari 《Cellular immunology》1982,67(1):60-73
Guinea pig peritoneal macrophages (GPPM) exhibited enhanced production of O2? and H2O2, and cytolytic activity toward erythrocytes, in response to reagents such as 12-O-tetradecanoyl-phorbol-13-acetate (TPA), its methylated derivative 4-O-MeTPA, Con A, wheat germ agglutinin (WGA), and opsonized zymosan. In order to examine the possible role of oxidative burst products such as O2? and H2O2 in the cytolytic process, we used reagents and enzymes which influence the balance of O2? and H2O2 outside and inside the GPPM cells. Macrophage-mediated cytolysis (MMC) of erythrocytes in the presence of the activators and modulators was assessed by 51Cr release assay. MMC activated by TPA and 4-O-MeTPA was inhibited by scavengers of H2O2 such as catalase and α-tocopherol, and was augmented by the catalase inhibitor 3-amino-1,2,4-triazole, and by horseradish peroxidase. TPA- and 4-O-MeTPA-activated MMC was only partially inhibited by the O2? scavenger cytochrome c and the enzyme superoxide dismutase and unaffected by cytochalasin D (an inhibitor of phagocytosis). MMC activated by the lectins Con A and WGA was unaffected by the scavengers and enzymes used, but markedly inhibited by cytochalasin D. Activation of MMC by TPA, WGA, and phagocytosis of opsonized zymosan, as well as O2? and H2O2 generation triggered by these reagents, were markedly inhibited by chlorpromazine. The results indicate that GPPM-mediated cytolysis activated by lectins, phorbol ester derivatives, and phagocytosis of opsonized zymosan, is dependent on the generation of oxidative burst products, mainly H2O2. TPA- or 4-O-MeTPA-activated MMC is mainly an extracellular event, while lectin-activated MMC may take place within the macrophages. 相似文献
9.
Iron-exposed murine macrophages have a modified bactericidal activity as shown by previous observations. In order to assess the role of iron in macrophage activation, as measured by free radical production and by intracellular bacterial killing, murine peritoneal macrophages were cultivated in the presence of various sources of iron, human iron-saturated transferrin and ammonium ferric citrate, or iron chelators, Desferal, and human Apo-transferrin, and were infected with an enteropathogenic strain ofE. coli. The release of nitrite (NO2 ?), and the production of superoxide anion (O2 ?) and hydrogen peroxide (H2O2) by the phagocytes were measured and compared to the production by uninfected macrophages. The synergistic action with murine r.IFN-γ was also studied in the radical production reaction and for the bactericidal activity of macrophages. Our results show that in vitro phagocytosis ofE. coli induced elevated production of NO2 ? and H2O2 by macrophages, and that oxygen derivatives were released independently of the presence of added iron or chelator. Despite a phagocytosis-related enhancement of NO2 ? release, reactive nitrogen intermediates (RNI) are not directly involved in the bactericidal mechanism, as revealed by increased intracellular killing owing to RNI inhibitors. Moreover, bacterial killing may depend on oxygen derivatives, as suggested by the effect of the antioxidant sodium ascorbate leading to both a diminished H2O2 production and a decreased bactericidal activity of macrophages. 相似文献
10.
Karthik Mallilankaraman Rajesh Kumar Gandhirajan Brian J. Hawkins Muniswamy Madesh 《Journal of visualized experiments : JoVE》2011,(58)
Oxidative stress has been implicated in a number of pathologic conditions including ischemia/reperfusion damage and sepsis. The concept of oxidative stress refers to the aberrant formation of ROS (reactive oxygen species), which include O2•-, H2O2, and hydroxyl radicals. Reactive oxygen species influences a multitude of cellular processes including signal transduction, cell proliferation and cell death1-6. ROS have the potential to damage vascular and organ cells directly, and can initiate secondary chemical reactions and genetic alterations that ultimately result in an amplification of the initial ROS-mediated tissue damage. A key component of the amplification cascade that exacerbates irreversible tissue damage is the recruitment and activation of circulating inflammatory cells. During inflammation, inflammatory cells produce cytokines such as tumor necrosis factor-α (TNFα) and IL-1 that activate endothelial cells (EC) and epithelial cells and further augment the inflammatory response7. Vascular endothelial dysfunction is an established feature of acute inflammation. Macrophages contribute to endothelial dysfunction during inflammation by mechanisms that remain unclear. Activation of macrophages results in the extracellular release of O2•- and various pro-inflammatory cytokines, which triggers pathologic signaling in adjacent cells8. NADPH oxidases are the major and primary source of ROS in most of the cell types. Recently, it is shown by us and others9,10 that ROS produced by NADPH oxidases induce the mitochondrial ROS production during many pathophysiological conditions. Hence measuring the mitochondrial ROS production is equally important in addition to measuring cytosolic ROS. Macrophages produce ROS by the flavoprotein enzyme NADPH oxidase which plays a primary role in inflammation. Once activated, phagocytic NADPH oxidase produces copious amounts of O2•- that are important in the host defense mechanism11,12. Although paracrine-derived O2•- plays an important role in the pathogenesis of vascular diseases, visualization of paracrine ROS-induced intracellular signaling including Ca2+ mobilization is still hypothesis. We have developed a model in which activated macrophages are used as a source of O2•- to transduce a signal to adjacent endothelial cells. Using this model we demonstrate that macrophage-derived O2•- lead to calcium signaling in adjacent endothelial cells. 相似文献
11.
We have reported previously that dihydropyridine-type calcium-channel antagonists (DTCCA) such as nifedipine decrease plasma
markers of oxidative stress damage in systemic sclerosis (SSc). To clarify the cellular basis of these beneficial effects,
we investigated the effects in vivo and in vitro of nifedipine on superoxide anion (O2
•-) production by peripheral blood monocytes. We compared 10 healthy controls with 12 patients with SSc, first after interruption
of treatment with DTCCA and second after 2 weeks of treatment with nifedipine (60 mg/day). O2
•- production by monocytes stimulated with phorbol myristate acetate (PMA) was quantified by the cytochrome c reduction method. We also investigated the effects in vitro of DTCCA on O2
•- production and protein phosphorylation in healthy monocytes and on protein kinase C (PKC) activity using recombinant PKC.
After DTCCA had been washed out, monocytes from patients with SSc produced more O2
•- than those from controls. Nifedipine treatment considerably decreased O2
•- production by PMA-stimulated monocytes. Treatment of healthy monocytes with nifedipine in vitro inhibited PMA-induced O2
•- production and protein phosphorylation in a dose-dependent manner. Finally, nifedipine strongly inhibited the activity of
recombinant PKC in vitro. Thus, the oxidative stress damage observed in SSc is consistent with O2
•- overproduction by primed monocytes. This was decreased by nifedipine treatment both in vivo and in vitro. This beneficial property of nifedipine seems to be mediated by its cellular action and by the inhibition of PKC activity.
This supports the hypothesis that this drug could be useful for the treatment of diseases associated with oxidative stress. 相似文献
12.
Kinetic analysis of superoxide anion production by activated and resident murine peritoneal macrophages 总被引:2,自引:0,他引:2
Using a continuous spectrophotometric assay, we have monitored the formation of superoxide anion (O2?) by activated and resident murine peritoneal macrophages. Macrophages elicited by injection with Corynebacterium parvum, as well as resident macrophages from untreated mice, were kept in suspension culture overnight to eliminate short-lived, contaminating neutrophils. Cytochemical analysis of the cultured macrophages disclosed that essentially all of the activated macrophages reduced nitroblue tetrazolium (NBT) dye vigorously. In contrast, only 18% of the resident macrophages demonstrated vigorous NBT reduction; the remainder of the resident macrophages reduced NBT very weakly. Kinetic analysis of macrophage O2? formation revealed that activated macrophages exposed to phorbol myristate acetate (PMA) produced O2? at a 13-fold greater maximum rate than resident macrophages. The decline in the rate of O2? production with time by activated macrophages was also greater than that of resident macrophages. The data indicate that the greater O2? production by activated macrophage populations is due to (i) the presence of an increased percentage of macrophages that respond to PMA with vigorous O2? production, and (ii) an increased maximum rate of O2? formation by these macrophages. 相似文献
13.
V. Fernández L. A. Videla 《Redox report : communications in free radical research》2013,18(5):317-321
SummaryAdministration of single doses of 0.1 mg of L-3,3′,5-triiodothyronine (T3)/kg for 3 consecutive day to fed rats elicited a marked increase both in the opsonized zymosan-induced luminal-amplified integrated chemiluminescence (ICL) of isolated polymorphonuclear leukocytes (PMN) in the absence (200%) and presence (228%) of L-arginine, and in the rate of superoxide radical (O2.-) production (180%). In the presence of L-arginine, the ICL was significantly increased by 57 and 17% over values observed in its absence, in PMN from control rats and T3-treated animals, respectively, an effect that was completely abolished by Nω-nitro-L-arginine. However, the net L-arginine-dependent ICL was comparable in stimulated PMN from both experimental groups, and the respective rates of nitric oxide (NO.) production were not significantly different, either in the absence or presence of nitro-L-arginine methyl ester. It is concluded that thyroid hormone-induced respiratory burst activity of rat PMN is not dependent on changes in NO. synthase activity, but rather on the adaptive increase in O2.- generation by NADPH oxidase. 相似文献
14.
In addition to superoxide (O2
.-) generation from nitric oxide synthase (NOS) oxygenase domain, a new O2
.- generation site has been identified in the reductase domain of inducible NOS (iNOS) and neuronal NOS (nNOS). Cysteine S-glutathionylation in eNOS reductase domain also induces O2
.- generation from eNOS reductase domain. However, the characteristics and regulatory mechanism of the O2
.- generation from NOS reductase domain remain unclear. We cloned and purified the wild type bovine eNOS (WT eNOS), a mutant of Serine 1179 replaced with aspartic acid eNOS (S1179D eNOS), which mimics the negative charge caused by phosphorylationand truncated eNOS reductase domain (eNOS RD). Both WT eNOS and S1179D eNOS generated significant amount of O2
.- in the absence of BH4 and L-arginine. The capacity of O2
.- generation from S1179D eNOS was significantly higher than that of WT eNOS (1.74:1). O2
.- generation from both WT eNOS and S1179D eNOS were not completely inhibited by 100nM tetrahydrobiopterin(BH4). This BH4 un-inhibited O2
.- generation from eNOS was blocked by 10mM flavoprotein inhibitor, diphenyleneiodonium (DPI). Purified eNOS reductase domain protein confirmed that this BH4 un-inhibited O2
.- generation originates at the FMN or FAD/NADPH binding site of eNOS reductase domain. DEPMPO-OOH adduct EPR signals and NADPH consumptions analyses showed that O2
.- generation from eNOS reductase domain was regulated by Serine 1179 phosphorylation and DPI, but not by L-arginine, BH4 or calmodulin (CaM). In addition to the heme center of eNOS oxygenase domain, we confirmed another O2
.- generation site in the eNOS reductase domain and characterized its regulatory properties. 相似文献
15.
Macrophage-mediated cytolysis off erythrocytes in the guinea pig. I. Activation by stimulators of the oxidative burst 总被引:2,自引:0,他引:2
Oxygen metabolites generated by macrophages may exert membrane injury to various cells. In this study reagents, which induce superoxide (O2?) and hydrogen peroxide (H2O2) production by paraffin oil elicited adherence purified guinea pig peritoneal macrophages (GPPM), were studied as to their potential to activate macrophage-mediated cytolysis (MMC) against allogeneic and autologous erythrocytes. Strong MMC reactions were activated by 12-O-tetra-decanoylphorbol-13-acetate (TPA), methylated TPA (4-O-MeTPA), opsonized zymosan, and out of six lectins tested, by wheat germ agglutinin (WGA) and concanavalin A (Con A). The cGMP elevators: sodium nitroprusside and sodium azide and the formyl-methionyl-type chemotactic peptides were ineffective. MMC activated by TPA, 4-O-MeTPA, WGA, and Con A was unaffected by colchicine and partially inhibited by cytochalasin B. TPA-activated MMC was abolished by diethyldithiocarbamate (DDC) (inhibitor of superoxide dismutase) and catalase, while WGA and Con A-activated MMC were only partially inhibited by DDC and unaffected by catalase. 相似文献
16.
The effect of mild hypoxic hypoxia on brain metabolism and acetylcholine synthesis was studied in awake, restrained rats. Since many studies of hypoxia are done with animals anesthetized with nitrous oxide (N2O), the effects of N2O were evaluated. N2O (70%) increased the cerebral cortical blood flow by 33% and the cortical metabolic rate of oxygen by 26%. In addition, the synthesis of acetylcholine in N2O-anesthetized animals, measured with [U-14C]glucose and [1-2H2,2-2H2]choline, decreased by 45 and 53%, respectively. Consequently, mild hypoxia was studied in unanesthetized rats. Control rats breathing 30% O2 (partial pressure of oxygen, Pao2= 120 mm Hg) were compared with rats exposed to 15% O2 (Pao2= 57 mm Hg) or 10% O2 (Pao2= 42 mm Hg). The synthesis of acetylcholine, measured with [U-14C]glucose, was decreased by 35 and 54% with 15% O2 and 10% O2 respectively; acetylcholine synthesis, measured with [1-2H2,2-2H2]choline, was decreased by 50 and 68% with 15% O2 and 10% O2 respectively. Animals breathing either 15% or 10% O2 had normal cerebral metabolic rates of oxygen but had increased brain lactates and increased cortical blood flows compared with animals breathing 30% O2. These results show that even mild hypoxic hypoxia impairs acetylcholine synthesis, which in turn may account for the early symptoms of brain dysfunction associated with hypoxia. 相似文献
17.
18.
Acetylcholine Synthesis and CO2 Production from Variously Labeled Glucose in Rat Brain Slices and Synaptosomes 总被引:4,自引:4,他引:0
Abstract: The molecular basis of the close linkage between oxidative metabolism and acetylcholine (ACh) synthesis is still unclear. We studied this problem in slices and synaptosomes by measurement of ACh synthesis from [U-14C]glucose, and 14CO2 production from [3,4-14C]- and [2-14C]glucose, an index of glucose decarboxylation by the pyruvate dehydrogenase complex (PDH) and the enzymes of the Krebs cycle, respectively. We examined both under conditions that either inhibited (low O2 or antimycin) or stimulated (2,4- dinitrophenol [DNP] or 35 mm -K+) 14CO2 production from [2-14C]- or [3,4-14C]glucose. Incorporation of [U-14C]glucose into ACh was reduced under low O2 and by antimycin or DNP (by 51-93%) and stimulated by 35 mm -K+ (by 30-60%). Under all of these conditions, ACh synthesis and the decarboxylation of [3,4-14C]- and [2-14C]glucose were linearly related (r= 0.741 and 0.579, respectively). The difference in the rate of 14CO2 production from [3,4-14C]- and [2-14C]glucose was used as a measure of the amount of glucose that was not oxidatively decarboxylated (efflux). We found that efflux was reduced (low 02 and antimycin), unchanged (DNP in slices), or increased (DNP in synaptosomes and K+ stimulation in slices) compared with control values under 100% O2. ACh synthesis and efflux were more closely related (r= 0.860) than ACh synthesis and 14CO2 production from variously labeled glucoses. 相似文献
19.
Steven L. Kunkel Kip Kaercher Micheal Plewa Joseph C. Fantone Peter A. Ward 《Prostaglandins & other lipid mediators》1982,24(6):789-799
Mononuclear phagocytes are knwon to play a key role in various phlogistic reactions by synthesizing and releasing products that may potentiate or inhibit inflammatory processes. The expression of these products appears to be dependent on the source of the macrophage population as well as the stimulus employed. We have studied superoxide anion (O2−) production as well as the generation of PGE2, PGF2α, and TXB2 from resident, oil-elicited and thiogylcollate-induced peritoneal macrophages in mice in the presence and absence of chemotactic peptides. Production of O2−, occurred only in elicited macrophages stimulated with high concentrations of FMLP or C5a; resident cells stimulated with either of the chemotactic peptides were completely unresponsive. Although resident peritoneal macrophages incubated with chemotactic peptides did not generate O2−, these cells did secrete significant levels of PGE2, PGF2α, and TXB2 in response to C5a. FMLP had no stimulatory effect. Elicited macrophages generated increased levels of PGE2 and PGF2α when incubated with C5a. However, production of TXB2 was not stimulated. FMLP was inactive in stimulating PGE2, PGF2α, and TXB2 in all types of macrophages studied. These studies indicate a heterogeneity in the production of inflammatory mediators from various macrophage populations in response to chemotactic factors. 相似文献
20.
Kobayashi T Ogawa Y Watanabe Y Furuya M Kataoka S Garcia del Saz E Tsunawaki S Dinauer MC Seguchi H 《Histochemistry and cell biology》2004,122(4):323-332
Macrophages produce superoxide (O2–) during phagocytosis or upon stimulation with a variety of agents including phorbol myristate acetate (PMA) through the activation of NADPH oxidase, and the formed O2– is converted to other reactive oxygen species (ROS) such as hydrogen peroxide (H2O2). The aim of the present study was to elucidate the effect of the intracellularly produced ROS on mitochondrial transmembrane potential (MTP) in mouse (C57BL/6) peritoneal resident macrophages stimulated with PMA. Using a fluorescent dye, succinimidyl ester of dichlorodihydrofluorescein (H2DCFDA), O2– was visualized in intracellular compartments in a certain subpopulation of macrophages isolated from wild-type mice. Cells deficient in gp91-phox, one of the membrane components of NADPH oxidase, were negative for the fluorescence. When cells were loaded with both H2DCFDA and MitoCapture, a fluorescent dye for mitochondria, mitochondrial fluorescence was diminished in O2–-producing cells, but not in O2–-deficient cells. Flow cytometry also revealed the decrease of mitochondrial fluorescence in wild-type cells, but not in gp91-phox-deficient cells. The loss of mitochondrial fluorescence was prevented by microinjection of catalase into cells. The present findings demonstrate that MTP is diminished by ROS, including the H2O2 dismutated from O2–, produced intracellularly by activation of the NADPH oxidase in mouse peritoneal resident macrophages stimulated with PMA. 相似文献