Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl
Ograniczanie wyników
Czasopisma help
Lata help
Autorzy help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 1030

Liczba wyników na stronie
first rewind previous Strona / 52 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  mice
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 52 next fast forward last
EN
The effectiveness of lithium in the treatment of affective disorders is well documented. However, the mechanism of this effect is still unknown. The purpose of this study was to investigate the effect of lithium on serotonergic neurons. The evaluation of the serotoninergic system activity was performed on the basis of an experimental model of head twitch response triggered by direct or indirect stimulation of serotonin 5-HT2 receptors in the brain. The obtained results indicated that the lithium chloride co-applied with a direct precursor of serotonin - 5-hydroxytryptophan used in a threshold dose and with carbidopa, generated head twitch response in mice. What is more, an enhancement of head twitch response in mice was observed after repeated 5-hydroxytryptophan application in head twitch-evoking doses. Moreover, inhibition of the serotonine storage in nerve endings in mice was evoked by reserpine administration. Furthermore, lithium increased the effect of 5-hydroxytryptophan given in a threshold dose and a head twitchevoking dose, respectively. In addition, when P-chlorphenylalanine (pCPA), an inhibitor of the serotonin synthesis within the serotonergic neurons, was given simultaneously with the lithium chloride, carbidopa and 5-hydroxytryptophan in the threshold dose, as well as with the lithium chloride and 5-hydroxytryptophan given at head twitchevoking dosage, pCPA administration decreased the number of head twitches responses in both experimental models, as well as in the reserpinized mice subjected to the lithium chloride and 5-hydroxytryptophan application. Finally, 5,7-dihydroxytryptamineevoked serotoninergic nerve endings destruction led to absolute inhibition of headtwitch response when observed after the lithium and 5-hydroxytryptophan application. Moreover, the increase by lithium 5-hydroxytryptophan-evoke head twitch response was inhibited by administration of the ritanserine - a 5-HT2 serotonin receptor blocking agent. In summary, our data show that lithium induced an enhancement of serotonergic neurotransmission due to its action on presynaptic serotonergic terminals.
EN
Activity of spleen lymphocytes derived from T. spiralis-infected C3H/w mice in the local GvH reaction was assessed using the popliteal lymph node GvH assay. It was found that splenocytes obtained on day 10 of the infection were substantially more active in the reaction than the spleen cells collected from uninfected donors. This effect correlated inversely with the infectious dose of the parasite, i.e. cells obtained from mice infected with 500 larvae per mouse were less efficient stimulators of the GvH reaction than splenocytes isolated from mice infected with 200 larvae per mouse. On day 30 of the infection activity of spleen T cells in the GvH reaction was suppressed in comparison to the control splenocytes but on day 60 post infection this activity returned to the baseline level. The above variations in the activity of splenic T lymphocytes in the local GvH reaction were readily quantitated by comparison of the three appropriate parameters assessed in the popliteal lymph nodes of both the infected and control animals and expressed as the mass, cellularity, and proliferation coefficients, respectively.
EN
Narciclasine is a 7-hydroxy derivative of lycorisidine. It was the first alkaloid isolated from the stem of narcissus (Amaryllidaceae) in 1967. Six mice were given narciclasine (5 mg/kg) by intravenous administration. A UPLC-MS/MS method was developed to determine narciclasine in mouse blood. Tectorigenin (internal standard, IS) and narciclasine were gradient eluted by mobile phase of methanol and 0.1% formic acid in a BEH C18 column. The multiple reaction monitoring (MRM) of m/z 308.1→248.1 for narciclasine and m/z 301.1→286.0 for IS with an electrospray ionization (ESI) source was used for quantitative determination. The calibration curve ranged from 1 to 6,000 ng/mL. The accuracy was from 92.5 to 107.3%, and the matrix effect was between 103.6 and 107.4%. The developed UPLC-MS/MS method was successfully applicated to a pharmacokinetic study of narciclasine in mice after intravenous administration (5 mg/kg).
EN
In this study, a precise, rapid, and accurate ultra-performance liquid chromatography–tandem mass spectrometer (UPLC–MS/MS) method for the quantitation of O-demethyl nuciferine in mouse blood was developed, and pharmacokinetics of O-demethyl nuciferine was studied for the first time after sublingual injection and gavage. The study was performed with an UPLC ethylene bridged hybrid (UPLC BEH) (2.1 mm × 50 mm, 1.7 μm) column at 30 °C, using diazepam as the internal standard (IS). The mobile phase consisted of acetonitrile–10 mmol/L ammonium acetate (containing 0.1% formic acid), with a flow rate of 0.4 mL/min for 4 min run time. Multiple reaction monitoring (MRM) modes of m/z 282.1→219.0 for O-demethyl nuciferine and m/z 296.2→265.1 for IS were utilized to conduct quantitative analysis. Protein in mouse blood was directly precipitated with acetonitrile for sample preparation. The linear range was 1–500 ng/mL with r > 0.995, and the lower limits of quantification (LLOQ) was 1 ng/mL. The intra- and inter-day precision of O-demethyl nuciferine in mouse blood were RSD < 14% and RSD < 15%, respectively.r The accuracy ranged from 89.0% to 110.7%, with a recovery higher than 88.9%, while the matrix effect was between 103.1% and 108.7%. We further applied this UPLC–MS/MS method to the pharmacokinetic study on O-demethyl nuciferine after sublingual injection and gavage and determined the bioavailability to be 6.4%.
EN
A novel arylsulfonamide derivative of aryloxy(propyl)piperidine PZ-1433, has been proved to possess a preclinical activity profile appropriate for the treatment of depression and memory impairments. In the present study its pharmacological activity toward anxiety symptoms as well as its anxiolytic properties have been examined in mouse and rat models. PZ-1433 significantly increased the number of punished crossings and decreased the number of buried marbles in two tests conducted in mice. Moreover, PZ-1433 evoked anxiolytic-like activity in “conditional” anxiety paradigm in rats, meaningly increasing the number of accepted shocks in the Vogel conflict drinking test. However, it did not produce a significant anxiolytic-like effect in “unconditional” anxiety model, i.e. the elevated plus-maze test. From these results, it is likely that direct antagonism toward serotonin 5-HT7 receptors may be involved in the anxiolytic action of PZ-1433. However, in vitro detected inhibition of serotonin transporter evoked by PZ-1433, might also contribute to this effect.
7
Content available remote Pharmacokinetics and bioavailability of liensinine in mouse blood by UPLC-MS/MS
88%
EN
Liensinine is a bisbenzyltetrahydroisoquinoline alkaloid extracted from lotus (Nelumbo nucifera GAERTNER., Nelumbonaceae), especially in its embryo loti “Lien Tze Hsin” (green embryo of mature seed). A rapid and simple UPLC-MS/MS method was developed to determine liensinine in mouse blood and its application to a pharmacokinetic study. The blood samples were preprocessed by protein precipitation using acetonitrile. Midazolam (internal standard, IS) and liensinine were gradient eluted by mobile phase of methanol and water (0.1% formic acid) in a Waters UPLC BEH C18 column. The multiple reaction monitoring of m/z 611.3 → 206.1 for liensinine and m/z 326.2 → 291.1 for IS with an electrospray ionization (ESI) source was used for quantitative detection. The calibration curve ranged from 0.5 to 400 ng/mL (r > 0.995). The accuracy ranged from 92.2 to 108.2%, the precision of intra-day and inter-day was less than 14%, and the matrix effect was between 100.0% and 109.6%, the recovery was better than 71.0%. The developed UPLC-MS/MS method was successfully used for a pharmacokinetic study of liensinine in mice after oral (5 mg/kg) and intravenous administration (1 mg/kg), and the absolute availability of liensinine was 1.8%.
EN
Diethylnitrosamine (DEN) is proven to be toxic to kidneys and liver and to act as a potent carcinogen mainly in liver. Capsaicin (CAP) is an alkaloid produced by Capsicum genus plants and is considered to be a protective agent against toxicity and carcinogenicity of many substances including DEN. The aim of this study was to assess the toxicity of DEN and CAP in liver and kidneys in mice. The experiment started after two weeks of acclimatisation and was conducted according to the Czech animal welfare protection legal guidelines. At the end of the experiment the mice were sacrificed and the toxicity of DEN and CAP in liver and kidneys were analysed. The histopathological examination of the liver revealed multifocal lymphoplasmacytic reaction in parenchyma in DEN treated group. CAP used as both preventive and therapeutic agent caused reduction in number and extent of lesions. In CAP group mitotic figures were found indicating xenobiotic-induced hepatotoxicity or regenerative changes. In the kidneys DEN revealed also multifocal lymphoplasmacytic reaction that has been mitigated by CAP. Moreover histopathological observation of the kidney in DEN group has revealed granular dystrophy of the renal tubules which has not been presented in CAP treated mice. Levels of ALT, AST activity, total protein and albumin concentration was not statistically different among control and experimental groups. In this study mild protective effect of CAP on DEN-induced hepatotoxicity and nephrotoxicity was shown only in histopathological changes. The toxicity of CAP itself is questionable and further studies should be performed to verify its chemopreventive potential.
EN
Essential polyunsaturated fatty acids (PUFAs) in the feed may affect the gastrointestinal microbiota. The present study investigated the effect of 35-day supplementation of mice diet with 5% concentration of high-ω-3 PUFAs in flaxseed with focus on intestinal metabolism of mice. Capillary isotachophoresis method was used for the assessment of the level of organic acids in the gut material and faeces. Supplementation of flaxseed increased the level of organic acids in the caecum (acetic, propionic, butyric and valeric acids) and faeces (lactic, acetic, butyric acids). The most significant effect was observed on day 28 of flaxseed supplementation. The investigated additive had a stimulatory effect on intestinal metabolism and fermentation activity of beneficial bacteria.
EN
A rapid and simple UPLC-MS/MS method was developed to determine toddalolactone in mouse blood and applied to measure the pharmacokinetics of toddalolactone in mice. Blood samples were first preprocessed by ethyl acetate liquid-liquid extraction. Oxypeucedanin hydrate (internal standard, IS) and toddalolactone were gradient eluted from a UPLC BEH C18 column using a mobile phase consisting of acetonitrile and water (0.1% formic acid). Using electrospray ionization (ESI) as the ionization source, multiple reaction monitoring was used to detect the precursor and product ions of m/z 309.2 and 205.2, respectively, for toddalolactone and of m/z 305.1 and 203.0 for IS, respectively, for quantitative detection. A calibration curve was run over the concentration range of 5–4,000 ng/mL (r > 0.995). The matrix effects ranged from 93.5 to 98.4%, and the recovery was higher than 77.3%. The precision was less than 13%, and the accuracy ranged from 90.9 to 108.4%. The developed UPLC-MS/MS method was successfully used for measuring the pharmacokinetics of toddalolactone in mice after oral (20 mg/kg) and intravenous administration (5 mg/kg), and the absolute bioavailability of toddalolactone was 22.4%.
EN
Grapefruit juice (GFJ), a commonly consumed dietary substance, has been shown to alter the disposition of several commonly used drugs. The available data on the effects of GFJ on the paracetamol pharmacokinetics and pharmacodynamics are at variance. The aim of this study was to evaluate the effect of a single or multiple dose of GFJ on some pharmacokinetics and pharmacodynamics aspects of orally given paracetamol (400 mg/Kg). Male mice were randomly divided into three equal groups: mice in the first group were given paracetamol; the second group was given a single oral dose (10 mL/Kg) of GFJ one hour prior to paracetamol administration; the third group was administered multiple oral doses of GFJ (10 mL/Kg) for five consecutive days, and on the last day it was treated with paracetamol. Blood samples were collected 10, 20, 30, and 40 min, and 1, 2, 4, 6 and 8 h after paracetamol administration for subsequent pharmacokinetic analysis. Some mice in the same three groups were also tested for their reactions to thermal (hotplate) and chemical (acetic acid induced – abdominal constriction) nociceptive stimuli. GFJ increased the plasma concentration and area under the plasma concentration curve of paracetamol, to a greater extent after a single dose than multiple doses. It also increased the reaction time in the hotplate test, and reduced abdominal constrictions. GFJ administration increased the plasma concentration and the analgesic effect of paracetamol in mice. The possible implications of these changes in humans and their clinical relevance need to be further investigated.
EN
In this report we present effect of pizotifen, an antagonist of serotonin (5-hydroxytryptamine; 5-HT) receptors, on P-induced convulsions in mice. Experiments were conducted on male mice Balby. Convulsive effect P was determined using the following measures: percentage of mice with seizures, the number of seizure episodes/2 h, the latency time of the beginning P-induced seizure activity in mice and P-induced seizure activity of mice determined by score of Racine. Pretreatment mice with pizotifen (0.5 mg/kg ip) did not prevent convulsive effect P, applied ip at the dose of 50 μmol/kg ip (59.3 mg/kg) but significantly shortened the latency time of the beginning of P-induced seizure activity of mice. We conclude that central serotonin receptors are involved in the mechanism of P-induced convulsions.
EN
In this study, maternal toxicity and developmental effects of exposure to Ascaris trypsin inhibitor were evaluated in mice. Pregnant BALB/c females were injected intraperitoneally by Ascaris inhibitor /AIT/ at 200, 300, and 400 mg/kg body weight/day, on days 12 to 15 of gestation (stage of fetal development). At day 19 of pregnancy, uterine contents were inspected for implantation sites, early resorptions (moles), living fetuses and dead fetuses. The living fetuses were weighed and examined for external, internal and skeletal abnormalities. The results showed that AIT induced maternal toxicity, evidenced by maternal deaths, abortions, bleeding from uterus and reduced body weight gain as compared to control (p <0.01). There were no differences between the control group and the rest of all groups investigated for total implantation sites and early resorptions. Fetotoxicity was observed as shown by the decrease in the number of living fetuses and mean fetal weight, a high rate of intrauterine fetal deaths, delayed skeletal ossification, occurrence of pathological changes of fetal organs and tissues. Only one type of congenital malformations (hydronephrosis) was noted in fetuses after injection of higher doses of AIT.
EN
The present study has examined the level of total IgA and antigen-specific IgA antibodies in serum and bile in various inbred strains of mice infected with Trichinella spiralis. These strains of mice differ in the speed at which they expel the adult worms from the gut. BALB/c and CBA mice expel adult worms faster than C3H and C57BL/6 mice. However, the CBA strain of mice is more resistant to the establishment of an initial infection of T. spiralis than BALB/c mice. While total serum IgA and bile sIgA concentrations correlated with the time course of the expulsion of adult worms, there was no similar correlation between IgA concentrations and the intensity of T. spiralis infection during the muscle phases of infection in any of the strains of mice investigated. Specific IgA antibodies in sera and sIgA antibodies in bile were measured by ELISA in C57BL/6 mice using crude somatic L1 muscle larvae (AgL1) and crude adult worm (AgAd) antigens. A pronounced increase in sIgA antibodies to AgL1 antigen was found by day 9 of infection in bile. However, a gradual increase in IgA in serum to AgAd antigen was observed from 6 till 24 DAI. Specific IgA response in serum to AgAd was much higher than to AgL1 and, in contrast the sIgA response in bile, was more pronounced to AgL1 than to AgAd. This result suggests that bile may also provide a valuable source of sIgA.
EN
Cross-resistance between Toxocara canis and Trichinella spiralis was studied in CBA/J mice exposed to varying doses of T. canis and 14 days later challenged with 400 larvae of T. spiralis. Intestinal burden of T. spiralis on day 7 post infection (PI) in mice given 25 ova of T. canis was 70% of challenge control burden, but in mice given 250 ova the burden was consistently below 20% of the control value. Male worms were preferentially expelled from mice exposed to T. canis. Recovery of muscle larvae was reduced in mice given 250 ova, but not in mice given 25 ova. Intestinal burdens of T. spiralis in T. canis-sensitized mice (250 ova) was 58% of the control values at 36 h PI, and most of the remaining worms were expelled between 5 and 7 days PI. Worms from mice given 250 ova released lower numbers of newborn larvae in vitro.
EN
Recently the increasing prevalence of gastrointestinal diseases, including neoplasm, has resulted in the necessity of characterising not only the tumours, but also healthy mucosa. Research into the morphological changes of healthy mucosa under different experimental conditions, including drugs, special diets and the use of probiotic bacteria, is greatly facilitated by the availability of animal models. In spite of the widespread use of mice in gastrointestinal research, there is a lack of information on the qualitative and quantitative histological characteristics of the intestinal mucosa of the mouse. The aim of this study was to assess the morphological characteristics and the postnatal development of the small intestine of wild type mice — C57BL/6J. The mice were aged either 5 weeks or 12 weeks. The 12-week-old mice had been weaned at the age of 5 weeks. After dissection the small intestine was divided into 5 equal portions and randomly chosen microscopical sections from each were stained with haematoxylin and eosin. The parameters describing the morphology of the small intestine (villus height, depth of the crypt, villus width near the crypt, width of the villus connective tissue near the crypt, thickness of the muscular layer and the height of the enterocytes and their nuclei) were evaluated under a light microscope. In both age groups the height and width of the villi decreased, while the thickness of the muscular layer increased in the distal direction. The height of the enterocytes decreased and the height of the enterocyte nucleus increased towards the colon in both age groups. The depth of the crypts was greater in the younger animals than in the older ones. Our data provides the baseline morphological description of the small intestinal mucosa in wild type mice, strain C57BL/6J, which can be used as a reference for testing the influence of drugs, toxins, nutrients and inborn mutations on the mouse intestine.
first rewind previous Strona / 52 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.