Biological and Pharmaceutical Bulletin
Online ISSN : 1347-5215
Print ISSN : 0918-6158
ISSN-L : 0918-6158
22 巻 , 6 号
選択された号の論文の22件中1~22を表示しています
  • Hiroshi AKIYAMA, Kaori HOSHINO, Maho TOKUZUMI, Reiko TESHIMA, Hironobu ...
    1999 年 22 巻 6 号 p. 551-555
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    Carrot juice was administered orally to BALB/c mice immunized intraperitoneally with dinitrophenylated(DNP)-OVA for about 1 month. The titers of DNP-specific IgE, DNP-specific IgG, and the levels of total IgE in mouse sera were determined. The DNP-specific IgE production by mice fed carrot juice was significantly ingibited. On the other hand, the DNP-specific IgG production and the level of total IgE in mice fed carrot juice were not significantly different from those in control mice. We also examined the effect of feeding carrots on immediate-type htpersensitivity. One hour after antigen stimulation, the ears of mice fed carrots swelled less than those of control mice. Furthermore, the rise in serum histamine in the mice fed carrots under active systemic anaphylaxis was lower than in controls.We then examined the pattern of cytokine production by spleen cells from mice followed by restimulation with DNP-OVA in vitro. The spleen cells from the mice fed carrots produced more interferon-γ than those form the control group. In contrast, the spleen cells from the mice fed carrots produced less interleukin-4 than those form the control group. Furthermore, the interleukin-12 production of the spleen cells from mice fed carrots was aslo higher than that of the control group. These findings suggest that feeding carrots improves the helper T cell(Th)1/Th2 balance, inhibiting specific IgE production and antigen-induced anaphylactic response.
  • Naoko KAWAKAMI, Hiroaki TAKEMASA, Naoki OKAMURA, Takao HAYAKAWA, Shun ...
    1999 年 22 巻 6 号 p. 556-560
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    Calyculin A, a protein phosphatase inhibitor, enhanced phorbol 12-myristate 13-acetate (PMA)-induced superoxide anion (O-2) producuction and translocation of the cytosolic NADPH oxidase factor, p47phox, to the plasma membrane in guinea pig polymorphonuclear leukocytes (PMNs). When PMNs were treated with 1-(5-isoquinoline-sulfonyl)-3-methyl-piperazine (H-7), a protein kinase C (PKC) inhibitor, after exposure to PMA, inhibition of O-2 production and translocation of p47phox to the membrane fraction in PMA-stimulated PMNs were observed. When calyculin A was added to the PMA-stimulated PMNs after the addition of H-7, O-2 production was again observed, and translocation of p47phox to the membrane fraction also occurred. The activity of NADPH oxidase, the amount of p47phox and the level of phosphorylation of p47phox in the membrane fraction prepared form PMA-stimulated PMNs, were reduced by the addition of the cytosol fraction from unstimulated PMNs.These reductions were attenuated by calyculin A. These results indicated that the active from of NADPH oxidase in PMNs can be reconstituted after the active complex of the enzyme has disappeared once, and that one of the mechanisms of regulation of this enzyme activity involves the phosphorylation of p47phox in the cyotosol and dephosphorylation of phosphorylated p47phox in the NADPH oxidase complex by protein kinase and protein phosphatase, respectively.
  • Kinuko TERADA, Wasuke KAMISAKO
    1999 年 22 巻 6 号 p. 561-566
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    A suspension of cultured cells of Asparagus officinalis fed L-phenyl-D5-alanine-2, 3, 3-D3 (D8-phe) and DL-phenylalanine-3, 3-D2 (D2-phe) yielded D-enriched asparenyol, 4-[5-(4-methoxyphenoxy)-3-penten-1-ynyl]phenol(1). A 1H-NMR spectral study indicated that incorporation of deuterium atoms into the chains of the products was restricted to the C-9 position. The molecular ion regions of the MS of D-enriched metabolites, 1(D8-200), 1(D8-100) and 1(D8-50), obtained from feeding experiments using 200 mg, 100 mg and 50 mg of D8-phe, respectively, coincided with the theoretical spectra. This confirmed that a single phenylalanine molecule supplies the nine carbon atoms in the -CH=CH-CH2-O-C6H4-O- moiety of 1. The biosynthetic sequence forming 1 as a norlignan class of metabolite is considered.
  • Shizuo NARIMATSU, Shigeo YAMAMOTO, Rika KATO, Yasuhiro MASUBUCHI, Tosh ...
    1999 年 22 巻 6 号 p. 567-571
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    Enzymatic formation of desipramine (DMI) and imipramine N-oxide (IMINO) was kinetically characterized in rat liver microsomes at pH 8.5 and 7.5 The formation of IMINO was quickly suppressed by the preincubation of microsomes at 37°C at pH 8.5, but the suppression was comparatively gentle at pH 7.5. In kinetic sutdies, the formation of DMI was monophasic at the two pH Points, and a substrate inhibition was observed at pH 8.5, but not at pH 7.5. In contrast, the formation of IMINO was biphasic at both pH points, i.e., the summation of a low-Km phase and a high-Km phase. Methimazole (MZ), an inhibitor of flavin-containing monooxygenase (FMO), markedly suppressed the low-Km phase of IMINO formation at both pH points. MZ also suppressed DMI formation at pH 8.5, but it elevated DMI formation at pH 7.5 SKF 525-A, an inhibitor of cytochrome P450 (CYP), markedly suppressed DMI formation at both pH points. The inhibitor suppressed IMINO formation in the high-Km phase of the biphasic kinetics at both pH points, whereas it stimulated the activity of the low-Km phase at pH7.5. These results suggest that CYP enzyme(s) are mainly reponsible for DMI formation at pH 8.5 and 7.5, and FMO enzyme(s) also are involved in IMI N-demethylation at a higher pH range in rat liver microsomes, at least in part. In the formation of IMINO, FMO is a major enzyme at both pH points, and CYP may also contribute to the N-oxide formation to some extent at pH 8.5.
  • Yuji ISHIKAWA, Hidekazu TAKENO, Kazuhiro WATANABE, Tadato TANI
    1999 年 22 巻 6 号 p. 572-576
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    HQL-975 (3-{4-[2-(5-methyl-2-phenyl-oxazol-4-yl)-ethoxy]-phenyl}-2S-propylamino-propionic acid) is a new oral antidiabetic agent which has been shown to be effective in insulin-resistant diabetic animals. In the present study, we examined the effects of HQL-975 on glucose utilization and insulin action in KK-Ay mice with genetically obese non-insulin diabetes. (1) Dietary administration of HQL-975 (19 mg/kg/d for 7d) improved hyperglycemia, hyperlipidemia and hyperinsulinemia in the mice. (2) The HQL-975-treated mice showed enhanced net glucose utilization, That is, glucose was significantly incorporated into total lipids in the white adipose tissue(WAT) and liver, and into glycogen in the diaphragn for the last 24 h of the drug administration period. (3)Treatment improved the decreased stimulative action of insulin in the epididymal WAT and the agent increased insulin-stimulated lipogenesis from both glucose and acetate. (4) Treatment also increased the activity of lipogenic enzymes such as glycerol-3-phosphate dehydrogenase and fatty acid synthetase. (5) In vitro exposure of WAT to HQL-975 enhanced lipogenesis in the presence of insulin.From these findings, we conclude that HQL-975 improves glucose utilization of KK-Ay mice through the enhancement of insulin action, which is associated with its lipogenic effects.
  • Satoko UKAWA-ISHIKAWA, Masako SEKI, Masataka MOCHIZUKI
    1999 年 22 巻 6 号 p. 577-581
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    Alkanediazohydroxides are the key intermediates of carcinogenic N-nitroso compounds, and exist as geometrical isomers. In this paper, the mutagenicity and cytotoxicity of (E)- and (Z)-potassium alkanediazotates, precursors of alkanediazohydroxides, in Chinese hamster V79 cells were investigated. Mutagenic and cytotoxic activities of (E)-diazotates were dose-dependent, and activity decreased with an increase in the alkyl chain length; methyl>ethyl>propyl, butyl. On the other hand, (Z)-diazotates were less mutagenic and cytotoxic than(E)-diazotates, however (Z)-potassium methanediazotate did show weak mutagenicity. To compare chemical reactivity with biological activity, alkylating activity towards incotinamide in an aqueous phosphate buffer system was evaluated as an index of the chemical reactivity of diazotates. Using a fluorometric HPLC method, alkylated nicotinamides were detected with high sensitivity in the reaction with all diazotates tested. The alkylting activity of (Z)-methanediazotate was higher than that of the corresponding (E)-diazotate, but the other isomers with ethyl, propyl and butyl groups had similar reactivity under the conditions used. The activity decreased by increasing the alkyl chain-length, which correlated well with the mutagenicity in V97 cells and also with that in Salmonella typhimurium, which we reported earlier. The results for (E)-diazotates were similar to the corresponding N-nitroso-N-(hydroxymethyl)alkylamines, further supporting the notion that α-hydroxy nitrosamines decompose through alkanediazohydroxide and alkylate DNA, and suggests that geometrical isomerism influences the carcinogenicity of N-nitroso compounds in mammals.
  • Yanmei LI, Koichi METORI, Katsuya KOIKE, Qing-ming CHE, Shushichi TAKA ...
    1999 年 22 巻 6 号 p. 582-585
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    We earlier reported that collagen synthesis in false aged model rats was stimulated by the administraion of a methanol extract from the leaves of Eucommia ulmoides OLIVER. When the methanol extract was fractionated to n-hexane, ethyl acetate, acetone and methanol fractions by silica gel chromatography, we discovered that geniposidic acid and sucubin, contained in the acetone fraction, were the active ingredients. In the current study, we set out to examine if active compounds found in the Eucommia ulmoides OLIVER leaf (EUOL) improved the low turnover rate in the stratum corneum of false aged model rats. The turnover rate in the stratum corneum in rats we measured as 50% dansyl chloride clearance day. In the first experiment, administration of a 2.4% water soluble methanol extract (WSME) of EUOL, along with an 11% protein diet, led to a 20% higher turnover rate in the stratum corneum (p<0.05, Mann-Whitney) than the control value. The WSME mainly contained iridoid mono-glycosides such as geniposidic acid. In the second experiment, treatment with geniposidic acid similarly caused a higher turnover rate in the stratum corneum, increasing turnover by 23% (p<0.05, Mann-Whitney)compared to the control value. In this paper we reveal that the WSME contains compounds effective against aging, and one of them is geniposidic acid.
  • Taiko ODA, Megumi EBATA, Shigenobu MATSUMOTO, Shiro URANO, Yoshihiro S ...
    1999 年 22 巻 6 号 p. 586-589
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    To elucidate the various activities of synthetic estrogens, the antioxidative activities of diethylstilbestrol(DES) and related metabolic analogs were examined. The antioxidative activities were assessed in terms of the inhibitory effect on Fe2+-and ascorbic acid-induced peroxidation of egg phosphatidylcholine (egg PC), and also superoxide scavenging ability using cyclic voltametry. Moreover, after in vivo administration of the test compounds to mice, the animals were subjected to hyperoxia, and catalase, glutathione peroxidase and superoxide dismutase activities in the brain, lungs and liver were measured. The results indicated that indenestrol A, one of the metabolites of DES, had the strongest antioxidative activity among the test compounds under both in vivo and in vitro conditions.
  • Fumihiko YAMAMOTO, Hidenobu OKA, Shigetoshi ANTOKU, Yu-ichi ICHIYA, Ko ...
    1999 年 22 巻 6 号 p. 590-597
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    In order to develop new imaging markers for brain hypoxia, two lipophilic nitroimidazoles, 1-(3-fluoropropyl)-2-nitroimidazole (FPN) and 1-(8-fluorooctyl)-2-nitroimidazole (FON) were synthesized and labeled with fluorine-18. The octanol/water partition coefficients were measured as an indication of lipophilicity, giving values of log P=0.28 for FPN and log P=2.72 for FON, respectively, which are in the range thought to be optimal for the diffusion of molecules across the blood-brain barrier. It was suggested from a comparative study of in vitro radiosensitization in V79 cells that these lipophilic analogs may have reduction potentials close to those of fluoromisonidazole (FMISO) and misonidazole (MISO), known hypoxic cell radiosensitizers. The preparation of 18F-labeled FON (18FON) and FPN (18FPN) was achieved via two-steps through [18F]fluoride ion displacement of tosylate precursors. in reasonable radiochemical yields. Tissue distribution of 18FPN and 18FON in normal rats and tumor-bearing mice after intravenous injection was investigated and compared to the behavior of 18F-labeled FMISO (18FMISO), a proven hypoxic imaging agent. The high lipophilicity of 18FON and 18FPN resulted in increased initial uptake into normal rat brain, relative to 18FMISO, followed by a rapid washout from brain. Both of these lipophilic analogs had significantly lower tumor uptake and lower tumor-to-blood rations than 18FMISO, suggestive of a poor trapping mechanism within the tumor tissue. Neither 18FON or 18FPN offers improved biological properties over 18FMISO as a potential agent for use in brain hypoxic imaging.
  • Michiho ITO, Mariko TOYODA, Akiko YUBA, Gisho HONDA
    1999 年 22 巻 6 号 p. 598-601
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    A new essential oil chemotype of Perilla frutescens was found in that plant variety form Che-ju island in Korea. The steam-distilled oil of this plant was examined by GC-MS and 32 compounds were identified. Its principal constituents were β-caryophyllene, dillapiol and nothoapiol. Also, crossing experiments were performed between the new chemotype and known chemotypes to clarify the genetic of the production of nothoapiol. The gene Na, which promotes conversion form dillapiol to nothoapiol, was suggested, and was considered to be closely linked with the allele D.
  • Midori TAKASAKI, Takao KONOSHIMA, Harukuni TOKUDA, Kazuo MASUDA, Yoko ...
    1999 年 22 巻 6 号 p. 602-605
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    An extract of the roots of Taraxacum japonicum (Compositae) exhibited strong anti-tumor-promoting activities on the two-stage carcinogenesis of mouse skin tumor induced by dimethylbenz[a]anthracene (DMBA) as an initiator and 12-O-tetradecanoylphorbol-13-acetate (TPA) as a promoter, as well as on that induced by DMBA and fumonisin B1. Further, the extract exhibited anti-tumor-initiating activity on the two-stage carcinogenesis of mouse skin tumor induced by (±)-(E)-methyl-2-[(E)-hydroxyimino]-5-nitro-6-methoxy-3-hexenamide (NOR-1) as an initiator and TPA as a promoter. These results suggested that an extract of the roots of the Taraxacum plant could be a valuable chemopreventive agent against chemical carcinogenesis.
  • Midori TAKASAKI, Takao KONOSHIMA, Karukuni TOKUDA, Kazuo MASUDA, Yoko ...
    1999 年 22 巻 6 号 p. 606-610
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    Eleven triterpenoids (1-11) form the roots of Taraxacum japonicum (Compositae) were examined for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) induced by the tumor promoter, 12-O-tetrade canoylphorbol-13-acetate (TPA), in Raji cells as a primary screening test for anti-tumor-promoters (cancer chemopreventive agents). Of these triterpenoids, traxasterol (1) and taraxerol (7) exhibited significant inhibitory effects on EBV-EA induction, but the inhibitory effects of their acetates 2 and 8 were weaker than those of and 7. Furthermore, 1 and 7 exhibited potent anti-tumor-promoting activity in the two-stage carcinogenesis tests of mouse using 7, 12-dimethylbenz[a]anthracene (DMBA) as an initiator and TPA as a promoter, and 1 showed a remarkable inhibitory effect on mouse spontaneous mammary tumors using C3H/OuJ mouse. These results strongly suggested that traxasterol (1) could be a valuable chemopreventive agent.
  • Isao SAKAI, Hideyuki TOZAKI, Keiko MATASUMOTO, Yukiko ITO, Takuya FUJI ...
    1999 年 22 巻 6 号 p. 611-615
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    The effects of formulation factors on the enhancement of colonic absorption of azetirelin by n-lauryl-β-D-maltopyranoside (LM) were studied in rats. Coadministration of LM with a small volume of azetirelin solution to the proximal colon increased the AUC of the drug by 8.7-fold. There were on significant differences in the LM-in-duced absorption profiles of azetirelin between unligated and ligated colon. The addition of a viscous polymer to the drug solution, which delayed the in vitro release of both azetirelin and LM, reduced the promoting effects of LM. These results suggest that the action of LM is not affected by sample spreading in the colonic lumen, whereas a rapid release of both azetirelin and LM from the formulation is necessary to maximize the efficacy of LM. Utilizing the balloon sonde method, the effects of LM were also confirmed in the colonic loop of dogs. Based on these results, an enteric capsule formulation of azetirelin containing LM and citric acid (CA), a potential inhibitor of the bacterial degradation of azetirelin in the distal intestine, was prepared and its performance was evaluated in fasted dogs. The bioavailability of azetirelin after the oral administration of this enteric capsule with LM and CA was 43.5% compared with a bioavailability of 14.9% in capsule without LM and CA. Therefore, the delivery of azetirelin and LM to the lower intestine, together with a rapid release of capsule contents, are feasible for the improved peroral bioavailability of azetirelin.
  • Tetsuya AIBA, Mary M TSE, Emil T LIN, Tamotsu KOIZUMI
    1999 年 22 巻 6 号 p. 616-622
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    Twelve healthy volunteers were given ibuprofen racemate in two different dosage forms, a suspension and a tablet. The plasma concentration-time profiles of S- and R-ibuprofen were determined and the R-ibuprofen inversion clearance was calculated. Although the area under the curve was almost the same in both the suspension and tablet studies, the inversion clearance was larger in the suspension study than in the tablet study (1.18±0.65 and 0.72±0.63l/h, shown as the mean±S.D.). The Michaelis-Menten parameters for this inversion process were then determined in vitro with human liver microsomes (1.3±0.2 mM for Km and 3.1±0.3 nmol/min/mg protein for Vmax, shown as the mean±S.D.). These parameters indicated that the stereoisomeric inversion of R-ibuprofen in the liver was not likely to be saturated at the plasma concentrations measured in the volunteer study. The profile of the plasma concentration ratio between S-ibuprofen and R-ibuprofen revealed a difference in the early phase of these two studies. Therefore the inversion defference between those two studies probably resulted from the difference in the absorption phase of each dosage form. Our study demonstrated that R-ibuprofen inversion could be affected by alteration of dosage from.
  • Tomomi HATANAKA, Theera RITTIROD, Kazunori KATAYAMA, Tamotsu KOIZUMI
    1999 年 22 巻 6 号 p. 623-626
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    A physical modeling and theoretical simulation aspect for the simultaneous transport and metabolism of prodrug in viable skin were described to understand the influence of enzyme distribution and diffusion. The physical model was formulated assuming that the viable epidermis and dermis have distinct diffusional and metabolic characteristics and that the metabolic reaction in each layer follows a first-order kinetics. The differential equations were analytically solved, and the steady-state flux of prodrug into receiver and that of metabolite into receiver and donor and the total flux in forward (epidermis to dermis) and backward (dermis to epidermis)directions were derived. The flux of prodrug in the forward direction always equals that in the backward direction. The metabolite flux into receiver became transport direction-dependent when the diffusional characteristic of epidermis was different from that of dermis regardless of enzyme distribution. The metabolite flux into donor in the backward direction relative to that in the forward direction increased with increase of dermis/epidermis ratio of any parameters among metabolic rate constant, partition coefficient and diffusion coefficient of prodrug and metabolite. The difference of total flux between the 2 transport directions was caused by the difference in metabolic rate constant, partition coefficient and diffusion coefficient of prodrug between epidermis and dermis. The higher any parameters were for dermis, the higher was total flux in the backward direction.
  • Kalpana SRIVASTAVA, Tomomi HATANAKA, Tetsuya AIBE, Kazunori KATAYAMA, ...
    1999 年 22 巻 6 号 p. 627-632
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    The purpose of this work was to investigate the disposition characteristics and pharmacodynamics of a benzodiazepine, oxazepam, in renal dysfunction rats. For the in vivo experiment, normal and renal dysfunction rats were given 40 mg/kg of oxazepam as the bolus dose. A quantitative electroencephalographic (EEG) method was used as the surrogate measure of the pharmacological response. The oxazepam concentration in plasma and cerebrospinal fluid (CSF) was assayed by the HPLC method. The steady-state volume of distribution and clearance based on total and unbound plasma did not change in renal dysfunction rats. Amplitude changes in the EEG induced by oxazepam in normal and renal dysfunction rats were characterized by a log-concentration response model or sigmoidal Emax model. The pharmacodynamic paramenters from these models were not altered in renal dysfunction. In vitro binding studies for γ-aminobutyric acid (GABA)-benzodiazepine receptor complx, the oxazepam-induced effect was not potentiated by the plasma dialysate form renal dysfunction rats. Thus, it was suggested that the brain sensitibity to benzodiazepines was not altered in renal insufficiency.
  • Tetsuya AIBA, Shin KUBOTA, Tamotsu KOIZUMI
    1999 年 22 巻 6 号 p. 633-641
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    To analyze the renal handing of therapeutic compounds observed as a non-linear process with a diffusion phenomenon, we employed a non-linear dispersion model described with a partial differential equation and solved it by using the finite difference method with an implicit scheme in a model dependent analysis. In this study, the renal handing of p-aminohippurate (PAH) was investigated in isolated perfused rat kidney, in which a 50 μl bolus of injection solution containing [3H]PAH and [14C]inulin was administered rapidly into the renal artery. The venous outflows were then collected for 15 min with a fraction collector. The renal extraction ratio of PAH was decreased from 65% to 18% as the PAH concentration in the injection solution was increased from 2 μM to 10 mM. The PAH outrlow profile changed as the extraction process became saturated. With the non-linear dispersion model, the Michaelis-Menten parameters for the PAH extraction process were estimated by a model fitting calculation. The calculated values were 0.83 μmol/min/kidney for Vmax and 89 μM for Km. It was demonstrated that the model dependent analysis with a non-linear dispersion model is a useful approach to characterize renal drug handing, and is probably applicable for examining other non-linear processes which involve a diffusion phenomenon.
  • Yaw-Bin HUANG, Jia-You FANG, Chen-Hsun HUNG, Pao-Chu WU, Yi-Hung TSAI
    1999 年 22 巻 6 号 p. 642-646
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    The in vitro and in vivo effect of pretreatment by cardamom oil, a crude drug extract, in ethanol/water vehicles on the transdermal delivery of indomethacin was investigated. The cyclic monoterpene components in cardamom oil were also determined and quantified in this study. The permeation of indomethacin was significantly enhanced after pretreatment of cardamom oil both in the in vitro and in vivo studies. The result of various pretreatment periods showed that the indomethacin flux decreased as the length of the pretreatment increased. Both natural cardamom oil and a cyclic monoterpene mixture composed of the components of the oil showed similar enhancement on indomethacin permeation, indicating cyclic monoterpenes are the predominant components altering the barrier property of stratum corneum. The results also showed that three minor components in cardamom oil (α-pinene, 6.5%; β-pinene, 4.8%; α-terpineol, 0.4%) had a synergistic effect with 1, 8-cineole (59.3%)and d-limonene (29.0%) to enhance the permeation of indomethacin.
  • Rie ISHII, Koichi SAITO, Masakazu HORIE, Takeshi SHIBANO, Susumu KITAN ...
    1999 年 22 巻 6 号 p. 647-653
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    An extract of Melastoma dodecandrum LOUR. with 80% aqueous acetone (MDL) inhibited nitric oxide (NO)production by a murine macrophage-like cell line, RAW264.7, activated with lipopolysaccharide (LPS) and recombinant mouse interferon-γ (IFN-γ). On further fractionation of the extract, the majority of the inhibitory activity was recovered in the 50% methanol extracts, which contained hydrolyzable tannins. Among the latter, casuarinin, casuarictin, pedunclagin and nobotannin B exhibited strong inhibitory activities toward NO production, with ID50 values between 2.0 and 5.11μM. Both MDL and the purified tannins significantly reduced the induction of the inducible nitric oxide synthase (iNOS) protein in the course of macrophage activation with LPS and IFN-γ. In addition, the NO production by macrophages preactivated with LPS and IFN-γ for 16 h was also inhibited by these tannins, with IC50 values around 30-130 μM, but not by MDL. These results suggest that MDL has the pharmacological ability to suppress NO production by activated macrophages and that the hydrolyzable tannins have major inhibitory activities.
  • Akihiro IMURA, Motohiro ITOH, Akihiko MIYADERA
    1999 年 22 巻 6 号 p. 654-656
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    The esterase form Micrococcus sp., which hydrolyzes n-propyl-2-fluorocyclopropanecarboxylate (3) enantioselectively, was highly purified by three types of chromatography. The purified enzyme was inactivated by Hg and diisopropyl fluorophosphate (DFP). It was a monomer with a molecular weight of about 35000. The enzyme exhibits esterase activity towards many aliphatic propyl esters. The enantioselectivity for substrate (3) using purified enzyme did not differ from that of crude enzyme.
  • Yuichi OZAWA, Masanori YOSHIZUMI, Daisuke INUI, Koichiro TSUCHIYA, Hit ...
    1999 年 22 巻 6 号 p. 657-659
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    We have studied the relationship between free and sulfoconjugated catecholamines (CAs) in the plasma of patients with various cardiovascular diseases and have described the physiological significance of sulfoconjugated CAs in plasma. In the present study, we measured free and sulfoconjugated dopamine (DA) and noradrenaline (NA) in the plasma of patients with atherosclerosis (AS). Results showed that the plasma levels of free DA and NA in patients with atherosclerosis were higher than those in control subjects. Moreover, it was also observed that the plasma levels of conjugated DA and NA in patients had a tendency to be higher than levels in control subjects. These results suggest the involvement of free CAs in atherosclerosis and that elevated free CAs may be converted to sulfoconjugated forms in patients with atherosclerosis.
  • Setsuko KUNIMOTO, Chisato NOSAKA, Tomio TAKEUCHI
    1999 年 22 巻 6 号 p. 660-661
    発行日: 1999/06/15
    公開日: 2008/04/10
    ジャーナル フリー
    XTT reducing activity by CHO and L1210 cells was found to be stimulated by the presence of cytochrome oxidase inhibitors such as NaN3 or KCN. Among the other respiratory chain inhibitors, antimycin A (a complex III inhibitor) and chlorpromazine inhibited cellular XTT reduction, and rotenone and malonate showed sligth inhibition and no effect, respectively. It is suggested that XTT reduction is coupled with the respiratory chain via cytochrome c, which is located between complexes III and IV (cytochrome oxidase).
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