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1.
Anidulafungin, an echinocandin, is currently approved for treatment of fungal infections in adults. There is a high unmet medical need for treatment of fungal infections in neonatal patients, who may be at higher risk of infections involving bone, brain, and heart tissues. This in vivo preclinical study investigated anidulafungin distribution in plasma, bone, brain, and heart tissues in neonatal rats. Postnatal day (PND) 4 and PND 8 Fischer (F344/DuCrl) rats were dosed subcutaneously once with anidulafungin (10 mg/kg) or once daily for 5 days (PND 4–8). Plasma and tissue samples were collected and anidulafungin levels were measured by liquid chromatography‐tandem mass spectrometry. The mean plasma Cmax and AUC0‐24 values were consistent with single‐dose plasma pharmacokinetics (dose normalized) reported previously for adult rats. Observed bone concentrations were similar to plasma concentrations regardless of dosing duration, with bone‐to‐plasma concentration ratios of approximately 1.0. Heart concentrations were higher than plasma, with heart to plasma concentration ratios of 1.3‐ to 1.8‐fold. Brain concentrations were low after single dose, with brain‐to‐plasma concentration ratio of approximately 0.23, but increased to approximately 0.71 after 5 days of dosing. Tissue concentrations were nearly identical after single‐dose administration in both PND 4 and PND 8 animals, indicating that anidulafungin does not appear to differentially distribute in this period in neonatal rats. In conclusion, anidulafungin distributes to bone, brain, and heart tissues of neonatal rats; such results are supportive of further investigation of efficacy against infections involving bone, brain, and heart tissues.  相似文献   

2.
探讨白芍总苷在正常大鼠体内的组织分布特点,为预测其药理作用及不良反应提供依据.正常大鼠按2.82 g/kg灌胃给予TGP药液后1、3、6h取心、肝、脾、肺、肾、胃、小肠、大肠等组织,各组织匀浆后,将匀浆液制成冻干粉,HPLC法测定冻干粉中芍药苷和芍药内酯苷浓度,计算各组织中两者浓度.结果显示1h各组织中均能测到芍药苷和芍药内酯苷,3h除胃和小肠外,其他各组织中两者浓度均达到最大值,小肠、胃、大肠及肾、脾、肝中浓度较高,6h小肠、大肠、胃中浓度较高,其他各组织中浓度较低.说明灌胃TGP后组织分布迅速且广泛,胃、小肠、大肠及肾、脾、肝是主要分布器官,容易在胃肠蓄积,其他组织中蓄积较少,为进一步研究白芍总苷的药理作用及作用机理提供了指导,同时为白芍归经理论提供了一定的现代科学依据.  相似文献   

3.
目的:研究重组人甲状旁腺素(1-34)[rhPTH(1—34)]在大鼠体内的组织分布和排泄情况,为进一步的临床实验提供参考。方法:用^125I-同位素示踪法结合TCA酸沉淀法测定各主要器官组织的总放射性浓度和酸沉淀部分放射性浓度,获得rhPTH(1-34)的尿粪排泄和胆汁排泄数据。结果:各主要器官组织的总放射性浓度排序由高到低依次为:尿、肾、膀胱、肠内容物、肌肉、血清、肾上腺、空肠、肝、肺脏、卵巢、肠淋巴结、脾、胸腺、心脏、脂肪、睾丸和脑;大鼠皮下注射。^125I-rhPTH(1-34)后,骨骼组织中放射性分布低于血浆,但消除缓慢,血浆浓度4h较15min降低了78%,而骨骼浓度多数仅降低了50%以下;注射后72h,尿、粪分别排出注入放射性量的73.6%±10.9%和3.2%±1.3%,尿、粪合计排出注入放射性量的76.8%±11,4%;注射后12h,胆汁中累积排出注入放射性的6.64%±1.04%。经分子筛排阻HPLC证实,^125I-rhPTH(1-34)不与大鼠的血浆蛋白发生结合。结论:rhPTH(1-34)在泌尿系统中的分布较高,在脂肪和脑中最低,提示药物不易透过血脑屏障;就全身放射性分布而言,在骨骼中分布较高,提示药物具有一定的靶向性;rhPTH(1-34)主要经尿的形式排泄。  相似文献   

4.
Berberine (BBR) has been confirmed to have multiple bioactivities in clinic, such as cholesterol-lowering, anti-diabetes, cardiovascular protection and anti- inflammation. However, BBR’s plasma level is very low; it cannot explain its pharmacological effects in patients. We consider that the in vivo distribution of BBR as well as of its bioactive metabolites might provide part of the explanation for this question. In this study, liquid chromatography coupled to ion trap time-of-flight mass spectrometry (LC/MSn-IT-TOF) as well as liquid chromatography that coupled with tandem mass spectrometry (LC-MS/MS) was used for the study of tissue distribution and pharmacokinetics of BBR in rats after oral administration (200 mg/kg). The results indicated that BBR was quickly distributed in the liver, kidneys, muscle, lungs, brain, heart, pancreas and fat in a descending order of its amount. The pharmacokinetic profile indicated that BBR’s level in most of studied tissues was higher (or much higher) than that in plasma 4 h after administration. BBR remained relatively stable in the tissues like liver, heart, brain, muscle, pancreas etc. Organ distribution of BBR’s metabolites was also investigated paralleled with that of BBR. Thalifendine (M1), berberrubine (M2) and jatrorrhizine (M4), which the metabolites with moderate bioactivity, were easily detected in organs like the liver and kidney. For instance, M1, M2 and M4 were the major metabolites in the liver, among which the percentage of M2 was up to 65.1%; the level of AUC (0-t) (area under the concentration-time curve) for BBR or the metabolites in the liver was 10-fold or 30-fold higher than that in plasma, respectively. In summary, the organ concentration of BBR (as well as its bioactive metabolites) was higher than its concentration in the blood after oral administration. It might explain BBR’s pharmacological effects on human diseases in clinic.  相似文献   

5.
孤儿受体G蛋白偶联受体15(GPR15)在哺乳动物肠道稳态以及炎症反应中发挥重要生理效应,但在非哺乳动物中,针对GPR15的研究几属空白。本文以家鸡Gallus gallus domesticus为模型,首次克隆了GPR15基因,并对其功能与组织表达进行了探究。结果显示:家鸡GPR15编码区cDNA长度为1 107 bp,由1个外显子组成,可编码368个氨基酸的受体蛋白。序列分析表明家鸡GPR15是具有7次跨膜结构的G蛋白偶联受体,且家鸡GPR15与人Homo sapiens、北美绿蜥蜴Anolis carolinensis、小鼠Mus musculus的GPR15具有约56%的氨基酸序列一致性;虽然系统进化树分析表明GPR15与爱帕琳肽受体(APLNR)有较近的进化关系,但在表达家鸡GPR15的HEK293细胞中,APLNR的内源性配体Apelin和Apela不能激活家鸡GPR15;此外,实时定量PCR分析发现GPR15在家鸡脾脏中高表达,在盲肠、肺中有中等水平表达,而在其他组织中微弱表达。上述结果为探究GPR15在禽类中的生理功能奠定了基础。  相似文献   

6.
The objective of this study is using radiolabelled PBN to determine the tissue distribution, excretion, and metabolism of PBN in rats in order to evaluate the effective time to trap free radical in appropriate tissue(s). Our results demonstrated that PBN is rapidly absorbed when it is injected intraperitoneally in the animal. PBN can be used as an effective spin trapping agent for a variety of tissues since it is evenly distributed among a wide range of tissues measured. Since there is no difference in the tissue concentrations and distribution pattern of PBN at 15, 30 and 60min after injection of PBN. it is appropriate to choose any of these time intervals to terminate the experiment and extract the spin adduct. The excretion of PBN, however, is slow. The majority of the radioactivity (70%) was excreted by the first 3 days. Only 5.7% of radioactivity was collected from 3 to 14 days. The remaining 25% of the radioactivity may be in the form of expired 14CO2. Trace amounts of radioactivity were recovered in the feces. PBN has probably only one major form of metabolite excreted in the urine. A small amount of the parent compound, however, was also excreted in the urine. The chemical structure of the metabolite(s) is still unknown.  相似文献   

7.
8.
通过已获得的多个物种IGF-1基因的cDNA序列,设计合成简并引物,用日本白鲫的肝脏总RNA反转录获得的cDNA做模板,克隆获得了IGF-1中间序列.在此基础上,通过SMART RACE,获得了IGF-1全长cDNA序列.经过序列对比分析,所得到的序列是日本白鲫(Carassius cuvieri)IGF-1 cDNA全长,其中开放阅读框为486 bp,编码含161个氨基酸的蛋白质,该蛋白质含有保守的信号肽、B、C、A、D和E结构域和6个半胱氨酸残基.同时,系统进化分析表明,在进化过程中IGF-1基因在鱼类中保持着高度保守的进化特征.IGF-1在日本白鲫中广泛表达于多个组织,尤其在肝脏中表达量最高.在垂体、心脏、肾脏和肌肉中有较高的表达.而在脑、脾脏、精巢和卵巢中的表达量较低.  相似文献   

9.
BESSESEN, DANIEL H, CONNIE L RUPP AND ROBERT H ECKEL. Trafficking of dietary fat in lean rats. Obes Res. 1995;3:191–203. Despite increasing interest in the role that fuel partitioning plays in determining body composition, the relative importance of oxidative versus storage pathways in the clearance of dietary fat remains unclear. A widely held view is that the primary destination of chylomicron triglyceride fatty acids (TGFA) is adipose tissue, and the primary source of lipid fuel for skeletal muscle is non-esterified fatty acids (NEFA). An alternate view is that muscle, not adipose tissue, is the primary site of TGFA clearance. This view is supported by estimates of the total lipoprotein lipase content of muscle and adipose tissue. To directly study the partitioning of dietary fat between oxidation and storage, 14C-labeled oleic acid was fed to Sprague Dawley rats and its metabolic fate followed over 30 days. Two hours after ingestion, more than 3.5 times as much label was found in skeletal muscle tissue (2.42 ± 0.45 nmols) and CO2 (0.25 ± 0.01 nmols) than was found in adipose tissue (0.71 ± 0.14 nmols). Intramuscular triglyceride was the lipid class most extensively labeled. After skeletal muscle, liver was the next most important site of TGFA clearance. Surprisingly a substantial quantity of label remained associated with the GI tract even 24 hours after ingestion. Between 2 and 10 days following ingestion there was a net decline in the C content of muscle, liver and GI tract, associated with a net rise in the 14C content of adipose tissue. These findings demonstrate: 1) the importance of skeletal muscle and liver in whole organism TGFA clearance, 2) the importance of intramuscular partitioning of lipid fuels between direct oxidation and storage as TG, 3) the potentially important role of the GI tract in the delivery of dietary fat to the circulation 10–24 hours following ingestion, and 4) the stability of adipose tissue as a storage site. The complex nature of the tissue-specific clearance of TGFA over time is perhaps better described by the term ‘trafficking’ than by the more commonly used term “partitioning.” Future studies of TGFA clearance combined with sampling of relevant tissues over time will provide insight into the specific roles that abnormalities in liver, muscle and adipose tissue TGFA metabolism play in the development of hypertriglyceridemic disorders and states of increased or reduced body weight.  相似文献   

10.
Glucosyl hesperidin (G-hesperidin) is a water-soluble derivative of hesperidin. We compared the absorption and metabolism of G-hesperidin with those of hesperidin in rats. After oral administration of G-hesperidin or hesperidin to rats, hesperetin was detected in sera hydrolyzed with β-glucuronidase, but it was not detectable in unhydrolyzed sera. Serum hesperetin was found more rapidly in rats administered G-hesperidin than in those administered hesperidin. The area under the concentration-time curve for hesperetin in the sera of rats administered G-hesperidin was approximately 3.7-fold greater than that of rats administered hesperidin. In the urine of both administration groups, hesperetin and its glucuronide were found. Urinary excretion of metabolites was higher in rats administered G-hesperidin than in those administered hesperidin. These results indicate that G-hesperidin presents the same metabolic profile as hesperidin. Moreover, it was concluded that G-hesperidin is absorbed more rapidly and efficiently than hesperidin, because of its high water solubility.  相似文献   

11.
王爱霞  方炎明 《植物研究》2011,31(4):478-488
以南京市常见行道树二球悬铃木为试材,通过对交通繁忙区和相对清洁区道路两边悬铃木叶和一年生枝条中6种重金属元素在组织水平分布的研究,揭示其在悬铃木各组织中可能的分布机理,以及对重金属可能的抵御机制。结果表明,置于空气污染下悬铃木叶片与一年生枝条各组织具有累积重金属元素的能力,且污染区相对含量高于清洁区(除Ni外);叶片各组织累积能力大小为下表皮>上表皮、海绵组织>栅栏组织。悬铃木一年生枝条表皮因具有皮孔、表皮毛和蜡质,故也有一定的重金属累积能力;悬铃木表皮系统是重要的重金属吸滞组织,且累积于表皮的重金属元素可通过表皮进入皮层和髓,这与一年生枝条内重金属元素的运输途径有关,具体运输机理有待于进一步探讨。根据悬铃木各组织重金属的分布,认为叶片和茎的表皮系统更能反映空气污染的真实情况,且这两种材料采集容易、破坏性小,建议在空气污染监测中大力采用。  相似文献   

12.
To examine the distribution of rice bran tocotrienol (T3), we gave rice bran T3 to rats after considering an acceptable daily intake of vitamin E for humans. Male SD rats (5 weeks of age) were fed for 3 weeks on a commercial diet containing 6.4 mg of vitamin E per 100 g wt and additively received vitamin E or the vehicle (vitamin E-free corn oil) by oral intubation. The animals were randomly divided into 4 groups depending on the type of test diet: control (vehicle), non-T3 (no T3 + 4.3 mg of tocopherol (TOC)/kg body weight (b.w.)/day), low-T3 (0.8 mg T3 + 3.5 mg TOC/kg b.w./day), and high-T3 (3.2 mg T3 + 1.1 mg TOC/kg b.w./day). The control rats and rats in the non-T3, low-T3, and high-T3 groups took 4.3 and 8.6 mg of vitamin E/kg b.w./day, respectively. Rice bran γ-T3 was significantly distributed to the adipose tissue and increased from 1.1 to 10.2 nmol/g of adipose tissue according to the rice bran T3 intake.  相似文献   

13.
Earlier studies have suggested that indoleamine 2,3-dioxygenase (IDO) has a wide tissue distribution in mammals. However, detailed information on its cellular localization and also the levels of expression in various tissues is still scarce. In the present study, we sought to determine the cellular localization of IDO and also to quantify the level of its expression in various mouse tissues by using the branched DNA signal amplification assay, Western blotting, and immunohistochemical staining. The highest levels of constitutive IDO expression were found to be selectively present in the caput of epididymis, except for its initial segment. IDO expression was also detected inside the luminal compartment and even in the stereocilia within this region. In the prostate, high levels of IDO were selectively expressed in the capsular cells. In addition, high levels of IDO expression were also selectively detected in certain types of cells in the placenta, spleen, thymus, lung, and digestive tract. Notably, the morphological features of most of the positively stained cells in these organs closely resembled those of antigen-presenting cells. Based on the tissue distribution and cellular localization characteristics of IDO, it is hypothesized that its expression may serve two main functions: one is to deplete tryptophan in an enclosed microenvironment (such as in the epididymal duct lumen) to prevent bacterial or viral infection, and the other is to produce bioactive tryptophan catabolites that would serve to suppress T-cell–mediated immune responses against self-antigens, fetal antigens, or allogeneic antigens, in different situations. (J Histochem Cytochem 58:17–28, 2010)  相似文献   

14.
Objective: To determine if adult female rats adapt to lower and higher dietary energy density. Research Methods and Procedures: Study 1 compared high‐fat (56%), high‐energy density (HD) (21.6 kJ/g) and high‐fat (56%), low‐energy density (LD) (16.0 kJ/g) diets before surgery (two groups, 2 weeks, n = 16) and after surgery [ovariectomy (O) Sham (S); 2 × 2 factorial, n = 8; 6 weeks]. The second study (no surgery) compared high‐fat (60.0%), high‐energy (22.0 kJ/g) and low‐fat (10.0%), low‐energy (15.1 kJ/g) diets (n = 8). Results: In study 1, food intake was similar for the first 2 weeks, but rats on the LD diet consumed less energy, gained less weight, and had lower nonfasted serum leptin (all p < 0.0001) than rats on the HD diet. After surgery, rats on the LD and HD diets had similar weight gain, but rats on the LD diet consumed more food (p < 0.0001) and less energy (p < 0.009). O rats consumed more food and gained more weight (p < 0.0001) than S rats. Results from study 2 were similar to those from study 1. Discussion: The results demonstrated that O and S surgery rats and rats with no surgery adjust their food intake to defend a level of energy intake. This defense only occurred after a 2‐week adaptation period. The major differences in final body weights and abdominal fat resulted from the initial 2 weeks before adaptation to energy density. Rats fed higher‐energy diets seemed to “settle” at a higher level of adiposity, and rats fed lower‐energy diets consumed more food to increase energy consumption.  相似文献   

15.
BESSESEN, DANIEL H, CONNIE L RUPP AND ROBERT H ECKEL. Dietary fat is shunted away from oxidation, toward storage in obese zucker rats. Obes Res. 1995;3:179–189. Previous measurements of lipoprotein lipase (LPL) activity in adipose tissue (ATLPL) of lean and obese Zucker rats have consistently documented increased activity in obese rats relative to lean. Since LPL is considered to be rate limiting for the delivery of triglyceride fatty acids (TGFA) to muscle and adipose tissue, these data have been used to suggest that the metabolic partitioning of TGFA favors storage over oxidation in obese rats. To document the partitioning of TGFA directly, the fate of 14C labeled oleic acid (42nmols) was fed to lean, obese, and obese Zucker rats fed a hypocaloric diet designed to chronically reduce weight 25% below that of obese controls (reduced-obese). The amount of 14C recovered in CO2 over 6 hours following ingestion was significantly less in obese rats compared to lean (0.45 ± 0.06 vs. 0.88 ± 0.09nmols, p=.0004) and less still in the reduced obese group (0.34 ± 0.06nmols p=.00003). Six hours after ingestion, the quantity of label found in adipose tissue was significantly greater in the obese rats compared to lean (14.51 ± 1.92 vs. 1.38 ± 0.29nmols p<.00001), but was intermediate in the reduced-obese group (9.23 ± 0.98nmols p=.0003). At 2.2 hours there was significantly more label in skeletal muscle of lean rats compared to either obese or reduced-obese (2.33 ± 0.24; 1.35 ± 0.04nmols p=.01; 1.41 ± 0.27nm p=.02). However, at 6 hours these differences between groups were no longer present. These findings Indicate that dietary fat is shunted away from oxidation toward storage in obese Zucker rats. Additionally it appears that there may be a relative block in the oxidation of TGFA that is taken up by skeletal muscle in obese rats. Finally the relative normalization of this partitioning defect in reduced-obese rats is at variance with what was suggested by previous measurements of tissue specific levels of LPL, and suggests an enhanced recirculation of fatty acids from adipose tissue to muscle in reduced-obese rats. This could occur through increased delivery of non-esterified fatty acids (NEFA) to muscle as a result of an increase in net lipolysis.  相似文献   

16.
Objective: To determine the effect of acute and chronic administration of a new food intake‐reducing compound (HMR1426) with novel mode of action (retardation of gastric emptying) on body weight development, food intake, and energy metabolism in rats. Research Methods and Procedures: Adult male Shoe‐Wistar rats were implanted with transponders allowing registration of body temperature (Tb) and locomotor activity. HMR1426 (10 or 50 mg/kg) was given orally, and acute (8 hours) and chronic (15 days) effects were measured on food intake, Tb, activity, total energy expenditure (indirect calorimetry), and epididymal adipose tissue mass. The effect of chronic treatment was compared with the effect of sibutramine (10 mg/kg). Results: HMR1426 (50 mg/kg) caused an acute and chronic decrease of food intake. There was no effect on the level and daily pattern of total energy expenditure, Tb, and locomotor activity. Respiratory quotient was acutely decreased by HMR1426 due to reduced food intake. Chronic treatment with HMR1426 decreased weight gain by 31% and epididymal white fat by 24%. Sibutramine caused a respective reduction of 48% and 35%. Energy efficiency was not affected by HMR1426 in contrast to sibutramine, which reduced energy efficiency and transiently increased activity. Discussion: HMR1426 showed an anorectic potential in rats and decreased body weight and fat mass. This was achieved solely by reducing food intake without influencing overall energy expenditure or behavior suggesting a peripheral mode of action. Thus, HMR1426 can be considered a potential new drug for obesity treatment.  相似文献   

17.
The determination of the abilities of flavonoids, hydroxycinnamates and phenolics to scavenge free radicals in vitro suggests potent combined antioxidant activities of fruits, vegetables, beverages and grains. However, the key question of uptake in humans has only recently been approached consistently. The study described here demonstrates the uptake of hydroxycinnamates, for the first time, and other phenolic components, applying an HPLC method for their detection in the urine of subjects consuming levels of specific fruit equivalent to an approximate intake of 25 mg flavonol glycosides.  相似文献   

18.
Summary Amphibian, avian and mammal tissues contain a nucleoside phosphotransferase clearly different from those previously described in vegetables and bacteria.Whatever the animal source, the enzyme showed many similar characteristics as far as substrate specificity, dependence upon Mg2+ instability at 37 °C, and the protecting effect of nucleotides were concerned. Moreover, when submitted to gel filtration, the enzyme behaved in all cases as a dissociable high molecular weight protein, whose degree of association was controlled by nucleotides.In amphibian and avian tissues multiple forms of the enzyme seem to be present which differ for the substrate concentration at half-maximal velocity (S0.5); the concentration of nucleotide effector which affords half-maximal protection at 37 °C (P0.5); and the Hill coefficient for monophosphate donor. Within each single species, the higher the interaction coefficient was, the lower S0.5 and P0.5 values were.In mammalian tissues one form of nucleoside phosphotransferase seems to prevail where cooperative interactions are almost absent and whose S0.5 as well as P0.5 values do not vary significantly from one tissue to another.  相似文献   

19.
Biological Trace Element Research - This study is aimed at evaluating the effect of dietary zinc-methionine (Zn-Met) supplementation during 3&nbsp;months prepartum up to 9&nbsp;months...  相似文献   

20.
Distribution of the citrus nematode (Tylenchulus semipenetrans) was studied over 18 months in a 6-year-old orchard of grapefruit (Citrus paradisi cv. Ruby Red) on sour orange (C. aurantium) rootstock. The 1.8-ha orchard was under chemical weed control, no tillage, and flood irrigation. Highest numbers of nematodes were found in the top 15 cm of the soil profile. The nematode population peaked in April and declined to lowest levels in August and September. Numbers of nematodes were negatively correlated (r = -0.95) with soil temperatures above 29 C. Soil populations of nematodes were not correlated with soil moisture. The distribution of the nematode in the field was highly skewed and was described by a negative binomial. In this 1.8-ha block, five soil samples of 12 cores each would provide an estimate within 20% of the true nematode population mean with 95% confidence.  相似文献   

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