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1.
Beta-glucosidase and beta-galactosidase activity profile tested in different seeds during 24 h germination revealed reasonably high levels of activity in Vigna radiata, Cicer arietinum, and Trigonella foenum-graecum. In all seeds tested, beta-galactosidase activity was, in general, higher than that of beta-glucosidase. T. foenum-graecum seedlings exhibited maximal total and specific activities for both the enzymes during 72 h germination. Se supplementation as Na2SeO3 up to 0.75 ppm was found to be beneficial to growth and revealed selective enhancement of beta-galactosidase activity by 40% at 0.5 ppm Se. The activities of both the enzymes drastically decreased at 1.0 ppm level of Se supplementation. On the contrary, addition of Na2SeO3 in vitro up to 1 ppm to the enzyme extracts did not influence these activities. Hydrolytic rates of beta-glucosidase in both control and Se-supplemented groups were enhanced by 20% with 0.05 M glycerol in the medium and 30% at 0.1 M glycerol. The rates were marginally higher in Se-supplemented seedlings than the controls, irrespective of added glycerol in the medium. In contrast, hydrolysis by beta-galactosidase showed a trend of decrease in Se-supplemented seedlings compared to the control, when glycerol was present in the medium. Addition of Se in vitro in the assay medium showed no difference in the hydrolytic rate by beta-galactosidase when compared to control, while the activity of beta-glucosidase declined by 50%. Se-grown seedlings showed an enhancement of transglucosidation rate by 40% in the presence of 0.1 M glycerol. The study reveals a differential response to Se among the beta-galactosidase and beta-glucosidase of T. foenum-graecum with increase in the levels of beta-galactosidase activity.  相似文献   

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In rats kept at an ambient temperature of 22 degrees C, centrally and peripherally administered sauvagine induces a dose-dependent hypothermia. To clarify the regulatory mechanisms and to ascertain which neurotransmitter systems mediate sauvagine-induced hypothermia, we administered sauvagine intracerebroventricularly and subcutaneously in rats pretreated with antagonists of muscarinic receptors (atropine), opiate receptors (naloxone), alpha-adrenoceptors (phentolamine, yohimbine and prazosin), beta-adrenoceptors (propranolol) and dopamine receptors (haloperidol and spiperone). Systemic pretreatment of rats with atropine, naloxone, prazosin and propranolol left sauvagine-induced hypothermia unaltered. Pretreatment with phentolamine (4 mg/kg, s.c.), a non-selective alpha-adrenoceptor antagonist, and yohimbine (3 mg/kg, s.c.), a selective alpha 2-adrenoceptor antagonist, enhanced the hypothermic action of sauvagine. Pretreatment with haloperidol (2 mg/kg, s.c.), a non-selective dopamine receptor antagonist, and spiperone (80 micrograms/kg, s.c.), a selective dopamine D2 receptor antagonist, significantly reduced the temperature fall induced by centrally (4 micrograms/rat) and peripherally (20 micrograms/kg) administered sauvagine. Thus, sauvagine-induced hypothermia appears not to be mediated by interactions with cholinergic, endogenous opiate or noradrenergic systems, but rather D2 dopaminergic pathways alone are involved in the inhibitory effect of sauvagine on body temperature in the rat.  相似文献   

4.
Potential involvement of brain endogenous angiotensin II in the nociception was investigated in mice by using ACE inhibitors and an angiotensin II antagonist. The mice were allocated to the groups which were orally treated with spirapril (5 mg/kg), trandolapril (5 mg/kg), enalapril (30 mg/kg), losartan (10 mg/kg), or vehicle for 1 day (single dose groups) and 7 days (repeated doses groups). Significantly longer jump latencies were obtained for the groups repeatedly treated with spirapril, trandolapril and losartan, while the group with enalapril gained no effect. In contrast, the single dosing of all agents failed to show antinociceptive effect. The brain ACE activity was determined ex vivo immediately after the hot-plate test, and showed to be suppressed for the groups repeatedly treated with spirapril or trandolapril. In the group repeatedly treated with losartan, ex vivo autoradiography depicted the marked decrease in angiotensin II-binding capacity to the sites containing exclusively AT1 receptors within the blood-brain barrier. The antinociceptive effects of repeated doses of spirapril and losartan were reversed by naloxone. These results suggest that brain endogenous angiotensin II is likely to be involved in central nociceptive mechanisms by its antagonistic interaction with endogenous opioid system.  相似文献   

5.
We stably expressed the rat D1A dopamine receptor in mouse fibroblast LTK- cells and obtained specific ligand binding and functional activity characteristic of the D1A dopamine receptor coupled to stimulation of adenylyl cyclase. In the transfected cells, the selective D1 agonist fenoldopam caused a concentration-dependent inhibition of Na+/K(+)-ATPase activity, achieving maximum inhibition of approximately 30%. The latter was abolished by the selective D1 antagonist (+)-SCH 23390 and by the specific protein kinase A inhibitor protein kinase inhibitor-(6-22) amide. In the nontransfected cells, fenoldopam did not affect Na+/K(+)-ATPase activity. 8-Chlorophenylthio-cAMP inhibited Na+/K(+)-ATPase activity in both transfected and nontransfected cells; this effect was blocked by protein kinase inhibitor-(6-22). These results indicate that the inhibition of Na+/K(+)-ATPase activity induced by agonist occupancy of D1A receptors is mediated by protein kinase A.  相似文献   

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PURPOSE: The present study was designed to examine the antinociceptive effects of orally administered ONO-9902, an enkephalinase inhibitor, on both somatic and visceral pain after visceral stress conditions. METHODS: Twenty six male rats were examined. Tail-flick (TF) and colorectal distension (CD) tests were used to determine somatic and visceral antinociceptive effects, respectively. Measurements were performed in rats under immediate post-stress conditions (group ST; n = 14) and in rats nor under stress conditions (group NST; n = 12). In the stressed group, the same device, CD, for visceral antinociceptive effects was used for visceral stress and was applied with an intracolonic pressure of 60 mmHg for 20 min after drug administration. The TF latency and CD threshold were measured before and at 30, 40, 50, 60 and 90 min after administration of ONO-9902 300 mg.kg-1 or distilled water. RESULTS: Orally administered ONO-9902 did not produce any changes in the % maximum possible effect (%MPE) in either TF or CD tests in the unstressed group. In the stressed group, %MPE in the CD test increased 18% and 31% at 30 and 40 min, respectively, after oral administration of ONO-9902 compared with the control group (P < 0.05). However, %MPE to TF test did not alter even after the CD-induced stress condition. CONCLUSION: These results suggest that ONO-9902 may have analgesic effects on visceral pain but not on somatic pain under immediate post-stress conditions.  相似文献   

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The suppressing effect of crude extracts of Tochu tea, an aqueous extract of Eucommia ulmoides leaves and a popular beverage in Japan, on the induction of chromosome aberrations in CHO cells and mice was studied. When CHO cells were treated with Tochu tea crude extract after MMC treatment, the frequency of chromosome aberrations was reduced. Out of 17 Tochu tea components, 5 irridoids (geniposidic acid, geniposide, asperulosidic acid, deacetyl asperulosidic acid, and asperuloside) and 3 phenols (pyrogallol, protocatechuic acid, and p-trans-coumaric acid) were found to have anticlastogenic activity. Since the anticlastogenic irridoids had an alpha-unsaturated carbonyl group, this structure was considered to play an important role in the anticlastogenicity. The anticlastogenic effect of Tochu tea extracts was examined in mice using a micronucleus assay. When mice received 1.0 ml 4% Tochu tea extract by oral gavage 6 h before intraperitoneal injection of MMC, a decrease in the frequency of micronuclei was observed. This decrease was not due to a delay in the maturation of micronucleated reticulocytes.  相似文献   

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The antinociceptive potency of dihydroetorphine in diabetic mice was examined. Subcutaneous administration of dihydroetorphine produced a dose-dependent antinociception in both non-diabetic and diabetic mice. The antinociceptive potency of s.c. dihydroetorphine was less in diabetic mice than in non-diabetic mice. The antinociception induced by i.c.v. dihydroetorphine (0.02 microgram) was also significantly less in diabetic mice than in non-diabetic mice. The antinociceptive effects of dihydroetorphine (10 micrograms/kg i.p.) in both diabetic and non-diabetic mice were significantly antagonized by s.c. administration of beta-funaltrexamine, a selective mu-opioid receptor antagonist. Furthermore, the antinociceptive effect of dihydroetorphine (10 micrograms/kg i.p.) in non-diabetic mice, but not in diabetic mice, was also significantly antagonized by naloxonazine, a selective mu 1-opioid receptor antagonist. The time course and the potency of the antinociceptive effect of dihydroetorphine (10 micrograms/kg i.p.) in diabetic mice were similar to those in naloxonazine-treated non-diabetic mice. Naltrindole, a selective delta-opioid receptor antagonist, or nor-binaltorphimine, a selective kappa-opioid receptor antagonist, had no significant effect on the antinociceptive effect of dihydroetorphine (10 micrograms/kg i.p.) in both diabetic and non-diabetic mice. These results suggest that dihydroetorphine produces an antinociceptive effect through the activation of both mu 1- and mu 2-opioid receptors in mice. Furthermore, the reduction in dihydroetorphine-induced antinociception in diabetic mice, as compared with non-diabetic mice, may be due to the hyporesponsive to supraspinal mu 1-opioid receptor-mediated antinociception in diabetic mice.  相似文献   

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The antinociceptive effect of L-arginine in streptozotocin-induced diabetic mice was examined. Although s.c. administration of L-arginine produced a dose-dependent inhibition of the tail-flick response in both non-diabetic and diabetic mice, the antinociceptive response was greater in diabetic mice than in non-diabetic mice. The antinociceptive effects of L-arginine in both diabetic and non-diabetic mice were significantly antagonized by s.c. administration of naltrindole, a selective delta-opioid receptor antagonist. However, neither beta-funaltrexamine, a selective mu-opioid receptor antagonist, nor nor-binaltorphimin ++, a selective kappa-opioid receptor antagonist, significantly affected the antinociceptive effect of L-arginine in diabetic and non-diabetic mice. These results suggest that L-arginine produces a marked antinociceptive effect in diabetic mice through the activation of delta-opioid receptors.  相似文献   

10.
OBJECTIVE: To identify characteristics associated with provision of bystander CPR in witnessed out-of-hospital cardiac arrest cases. METHODS: An observational, prospective, cohort study was performed using cardiac arrest cases as identified by emergency medical services (EMS) agencies in Oakland County. MI, from July 1, 1989, to December 31, 1993. All patients who sustained a witnessed arrest prior to arrival of EMS personnel were reviewed. RESULTS: Of the 927 patients meeting entry criteria, the 229 patients receiving bystander CPR were younger: 60.9 +/- 14.7 vs 67.9 +/- 14.7 years (p < 0.01). Most (76.6%) cardiac arrests occurred in the home. In a multivariate logistic model, only the location of arrest outside the home was a significant predictor of receiving bystander CPR [odds ratio (OR) 3.8; 99% CI 2.5, 5.9]. Arrests outside the home were associated with significantly improved outcome, with 18.2% of out-of-home and 8.2% of in-home victims discharged from the hospital alive (OR 2.5; 99% CI 1.4, 4.4). CONCLUSION: Patients who have had witnessed cardiac arrests outside the home are nearly 4 times more likely to receive bystander CPR, and are twice as likely to survive. This observation emphasizes the need for CPR training of family members in the authors' locale. This phenomenon may also represent a significant confounder in studies of out-of-hospital cardiac arrest and resuscitation.  相似文献   

11.
Y Cao  Y Wang  H Jin  A Wang  M Liu  X Li 《Canadian Metallurgical Quarterly》1996,21(11):687-8 inside back cover
The alcoholic extract of roots of Rllbus crataegifolius can inhibited the swellfoot by albumen, and reduce the capillary permeability of pertoneum and the edematous swelling of ears in mice. The extract also facilitates the extinction of hind paw edema induced by carrageenin and inhibits the cotton pellets granuloma formation in rats.  相似文献   

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Greener synthesis of ionic liquid(IL) assisted lanthanum oxide(La_2O_3) nanoparticles(NPs) was followed using Andrographis paniculata leaves extract by hydrothermal method at low temperature,The IL assisted La_2O_3(La_2O_3-IL) NPs were characterized by various properties such as structural,spectral,optical,morphological,and biological studies.Powder X-ray diffraction studies confirm that La_2O_3-IL NPs crystallize in the form of body-centered cubic structure and average crystalline size is shown-43 nm.FTIR and Laser Raman spectroscopy confirm the La-O,O-H and various functional groups.The La-O stretching vibration band attributes at 639 cm~(-1).The optical property of La_2O_3-IL NPs was characterized by UV-Vis and photo luminesce nce spectroscopy.The sharp and intense absorbance peak observed in the UV region at 288 nm can be assigned.In the PL spectrum,we observe two different emission bands like blue and green emission.The morphological and particle size determination were investigated by SEM with EDX spectra and TEM analyses.The agglomerated particles of hexagonal,spherical,and parallelogram shape are observed in the TEM images.The chemical elements,binding energies as well as La metal states on the surface of these synthesized NPs were determined using XPS.La_2O_3 NPs for good biological activities regarding antibacterial and anti-inflammatory potentials could be utilized in different biological applications to the food and biomedical industries.La_2O_3-IL has a high percentage of inhibitions than La_2O_3 and standard diclofenac.  相似文献   

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目的:探讨胡桃楸水提物(juglans mandshurica maxim extract,JMME)的抗诱变作用,及评价胡桃楸是否具有遗传毒性.方法:取80只昆明小鼠,随机分成不同JMME剂量的诱变组(6.55、13.09、26.18 g/kg,分别为1/8、1/4、1/2 LD50),不同剂量的JMME与环磷酰胺(cyclophosphamide,CP)(0.04 g/kg)联合应用的抗诱变组,阴性对照组(Ns)和阳性对照组(CP,0.04 g/kg),共8组,每组10只.采用小鼠骨髓细胞微核试验(MNT)检测JMME是否具有遗传毒性及抗诱变作用.结果:阳性对照组微核发生率(28.82‰)明显高于阴性对照组(2.65‰),其差异具有统计学意义(P<0.01),而JMME各剂量组与阴性对照组间的差异无统计学意义(P>0.05).抗诱变各组的微核发生率与阳性对照组比较,除JMME低剂量组(6.55 g/kg)无统计学意义外(P>0.05),JMME中剂量组(13.09 g/kg)和高剂量组(26.18 g/kg)均显著低于阳性对照组(P<0.05),其中高剂量组明显低于中剂量组(P<0.05).结论:在本实验条件下,JMME无遗传毒性,JMME对CP诱发的微核率,具有一定抵抗作用,且呈量-效关系.  相似文献   

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Methanolic extract (CM-ext) from tubers of Corydalis turtschaninovii forma yanhusuo has been screened for activity in experimental models of types I-IV allergy. In type I allergic models, CM-ext at doses of 200, 500 mg/kg, p.o. inhibited 48-h homologous passive cutaneous anaphylaxis (PCA) in rats which is related to IgE, and 4-h heterologous PCA in guinea pigs which is related to IgG. The inhibition of CM-ext on 48-h PCA was also recognized in adrenalectomized rats. CM-ext exhibited the inhibitory effect on formation of IgE antibody in BALB/c mice. In type II allergic model, it was found that CM-ext inhibits reversed cutaneous anaphylaxis (RCA). In type III allergic model, CM-ext showed the inhibitory effect on direct passive arthus reaction (DPAR) in rats. Furthermore, in type IV allergic model, CM-ext had the inhibitory effects on induction phase and effector phase in picryl chloride-induced contact dermatitis (PC-CD). It also showed therapeutic action on PC-CD. These results indicated that CM-ext not only inhibits antibody-mediated allergic reactions but also influences cell-mediated allergic reactions and should be recognized as a potent material for allergic reactions, although the mechanisms and active principles of CM-ext have not yet been completely determined.  相似文献   

15.
Cardioprotective effects of a standardized extract from leaves with flowers of Crataegus (WS-1442; content of oligomeric procyandins [OPC]: 18.75%) have recently been demonstrated in an ischemia-reperfusion model in rats. Further studies were now conducted to clarify the mechanism of action and to identify active constituents involved in these effects of WS-1442. Exhausting partitioning between ethyl acetate/water and successive ultrafiltration of the aqueous layer led to the quantitative recovery of three fractions, which were tested for their in vitro radical scavenging (RS) and human neutrophil elastase (HNE) inhibitory activity. The lipophilic ethylacetate-soluble fraction A, enriched in flavone derivatives and constituting 14.9% of WS-1442, was as active as WS-1442 in inhibiting HNE. However, its RS activity was only about half that of the primary extract. Although 67.9% of WS-1442 was recovered in a water-soluble low molecular weight fraction B, this fraction displayed only weak RS and HNE inhibiting activity. In contrast, the RS and HNE inhibiting potencies of an essentially flavone-free and OPC-rich fraction C (21.3% of WS-1442) were significantly higher (inhibition of lipid peroxidation: IC50 0.3 microgram/ml; inhibition of HNE: IC50 0.84 microgram/ml) as those of WS-1442. The RS and HNE inhibitory activities of the extract and those of its fractions correlated well with their OPC-content but not with their concentration of flavonols. These results demonstrate that OPCs of Crataegus extracts possess stronger radical scavenging activities than flavone derivatives or other constituents. In addition, the oligomeric components are potent inhibitors of HNE. Oral administration of 20 mg/kg/d of the OPC-rich fraction C to rats afforded similar protection against ischemia-reperfusion induced pathologies as treatment with WS-1442 at a dose of 100 mg/kg/d. These observations indicate that radical scavenging and elastase inhibitory activities could indeed be involved in the observed cardioprotective effects of WS-1442, and demonstrate that OPCs are major orally active constituents of WS-1442. Thus, Crataegus extracts used therapeutically for cardiovascular diseases should be analyzed and standardized for their OPC-content.  相似文献   

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Tobacco consumption is a worldwide problem. The recent increase in the consumption of the smokeless tobacco products (snuff and chewing tobacco) has stimulated interest into the carcinogenic effects of these forms of tobacco. The use of smokeless tobacco products has increased in popularity as the use of cigarettes has become less socially acceptable. For most individuals the use of tobacco is a chronic process. Therefore, the effects of an aqueous extract of smokeless tobacco (STE) in rats following low-dose exposure were examined. Female Sprague-Dawley rats were treated orally with 25 mg STE/kg every other day for 90 days. In order to obtain information regarding the cytotoxicity of STE, the ultrastructural changes occurring in livers of rats following administration of STE were examined under light and electron microscopy. Electron microscopy revealed that in the perisinusoidal spaces an accumulation of indistinct filamentous material occurred following 60 days of treatment, occupying most of the sinusoids. Moreover, the lipids were in a state of disintegration. Significant increases in 90 kDa protein expression were also observed due to chronic treatment with STE. Western blot analysis using a polyclonal mouse antibody against heat shock/stress protein 90 (HSP90) confirmed that the overexpressed proteins were heat shock/stress proteins (HSPs). The HSPs are believed to serve as adaptive or survival functions involving a rapid but transient reprogramming of cellular metabolic activity to protect cells from oxidative damage.  相似文献   

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The antinociceptive effect of 3 alpha-tropyl 2-(p-bromophenyl)propionate [(+/-)-PG-9] (10-40 mg kg-1 s.c.; 30-60 mg kg-1 p.o.; 10-30 mg kg-1 i.v.; 10-30 micrograms/mouse i.c.v.) was examined in mice, rats and guinea pigs by use of the hot-plate, abdominal-constriction, tail-flick and paw-pressure tests. (+/-)-PG-9 antinociception peaked 15 min after injection and then slowly diminished. The antinociception produced by (+/-)-PG-9 was prevented by the unselective muscarinic antagonist atropine, the M1-selective antagonists pirenzepine and dicyclomine and the acetylcholine depletor hemicholinium-3, but not by the opioid antagonist naloxone, the gamma-aminobutyric acidB antagonist 3-aminopropyl-diethoxy-methyl-phosphinic acid, the H3 agonist R-(alpha)-methylhistamine, the D2 antagonist quinpirole, the 5-hydroxytryptamine4 antagonist 2-methoxy-4-amino-5-chlorobenzoic acid 2-(diethylamino)ethyl ester hydrochloride, the 5-hydroxytryptamin1A antagonist 1-(2-methoxyphenyl)-4-[4-(2-phthalimido)butyl]piperazine hydrobromide and the polyamines depletor reserpine. Based on these data, it can be postulated that (+/-)-PG-9 exerted an antinociceptive effect mediated by a central potentiation of cholinergic transmission. (+/-)-PG-9 (10-40 mg kg-1 i.p.) was able to prevent amnesia induced by scopolamine (1 mg kg-1 i.p.) and dicyclomine (2 mg kg-1 i.p.) in the mouse passive-avoidance test. Affinity profiles of (+/-)-PG-9 for muscarinic receptor subtypes, determined by functional studies (rabbit vas deferens for M1, guinea pig atrium for M2, guinea pig ileum for M3 and immature guinea pig uterus for putative M4), have shown an M4/M1 selectivity ratio of 10.2 that might be responsible for the antinociception and the anti-amnesic effect induced by (+/-)-PG-9 through an increase in acetylcholine extracellular levels. In the antinociceptive and antiamnesic dose range, (+/-)-PG-9 did not impair mouse performance evaluated by the rota-rod test and Animex apparatus.  相似文献   

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Vicia faba L.seedlings were hydroponically cultivated in 0-12 mg/L of extraneous lanthanum(La) for 15 d to investigate ecotoxicological effects and risk assessment of rare earth elements(REEs).The results showed that reactive oxygen species(ROS) production suchas superoxide radical(O2.-) and hydrogen peroxide(H2O2) were overproduced at higher concentrations of La,resulting in oxidatively modified proteins and shoot growth retardation.While,superoxide dismutase(SOD),catalase(CAT),ascorbate peroxidase(APX) and guaiacolperoxidase(GPX) isoenzymes were elevated to some extent to eliminate excess of ROS.HSP70 production and endopeptidase isoenzymeswere also enhanced,which were involved in repairing or degradation of the oxidatively modified proteins due to La.Thus,the antioxidantisoenzymes,endoprotease isoenzymes and HSP70 worked cooperatively to alleviate the La-induced oxidative damage.The significant enhancement of CAT and APX isoenzymes and HSP70 could also be used as early bioindicators of La-polluted solution.The threshold doserange was firstly delimited as 1-2 mg/L of extraneous La,corresponding to 7.34-9.37 μg/g dry weight in the leaves.These results would behelpful to further understand the toxicological effects and possible mechanisms of REE(s) on crop seedlings.  相似文献   

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