Search results for " strain"
showing 10 items of 868 documents
Covalent DNA adducts formed in mouse epidermis by benzo(g)chrysene
1996
The metabolic activation in mouse skin of benzo[g]chrysene (B[g]C), a moderately carcinogenic polycyclic aromatic hydrocarbon (PAH) present in coal tar, was investigated. Male Parkes mice were treated topically with 0.5 micromol B[g]C and DNA was isolated from the treated areas of skin at various times after treatment and analysed by 32P-post-labelling. Seven major adduct spots were detected, at a maximum level of 6.55 fmol adducts/microg DNA. Mouse skin treated with the PAH benzo[c]phenanthrene (B[c]Ph) gave a total of 0.24 fmol adducts/microg DNA. B[g]C-DNA adducts persisted in skin for at least 3 weeks. Treatment of mice with 0.5 micromol of the optically pure putative proximate carcinog…
Comparative tumorigenicity of picene and dibenz[a,h]anthracene in the mouse
1990
The carcinogenic activity of the two polycyclic aromatic hydrocarbons (PAHs), picene (benzo[a]chrysene) and dibenz[a,h]anthracene (DBA), was determined in NMRI mice by five different experimental protocols in order to find out if picene is a carcinogen as predicted by recent quantum mechanical calculations in contrast to earlier observations which could not confirm any carcinogenic activity of picene. Single s.c. treatment of adult mice with picene or DBA (308 nmol/animal, each) led to the formation of fibrosarcomas in 63.3% of treated animals regardless of the PAH used. Chronic epicutaneous application of both PAHs (total dose 1.36 mumol) to the back of mice resulted in the development of …
Metabolism of 3-hydroxychrysene by rat liver microsomal preparations
1990
3-Hydroxychrysene, a metabolite of the polycyclic aromatic hydrocarbon (PAH) chrysene, was metabolised by rat liver microsomal preparations obtained from Arochlor 1254-pretreated rats. Eight major metabolites were isolated by high performance liquid chromatography and characterised by u.v. spectroscopy and a variety of mass spectrometric techniques. The metabolites were unambiguously identified as 9-hydroxy-trans-1,2-dihydroxy-1,2-dihydrochrysene and 9-hydroxy-r-1,t-2,t-3,c-4-tetrahydroxy-1,2,3,4-tetrahydrochrysene and tentatively identified as 3-hydroxy-trans-5,6-dihydroxy-5,6-dihydrochrysene (since chrysene is a symmetrical molecule the 3- and 9-positions are equivalent), 9-hydroxy-trans-…
Interaction of morphine and haloperidol on agonistic and motor behaviors of male mice.
1997
To further clarify the interaction between opioid and dopaminergic systems, the effects of simultaneous administration of morphine hydrochloride (1.25 or 2.5 mg/kg) and haloperidol (0.1 mg/kg) on aggressive behavior of male mice were explored. Isolated male mice (experimental animals) were confronted in a neutral area with anosmic, group-housed consepecifics (standard opponents) 30 min after injection of both compounds, and aggression was evaluated by estimation of times allocated to 11 different behavioral categories. In the first experiment (which functioned as a pilot study), the two doses of morphine were explored. In the second one, incorporating a more complete experimental design, on…
Gender differences in escape-avoidance behavior of mice after haloperidol administration.
1993
Gender differences in the disruptive effects of haloperidol on some reinforced behaviors have been observed in different species. However, the inhibitory action of haloperidol on the acquisition and performance of escape-avoidance behavior has only been investigated in male subjects. The present experiment was designed to investigate possible gender differences in the effects of haloperidol on the initial phase of an escape-avoidance learning task. Male and female mice of the OF1 strain were given a single training session in a shuttle-box. Thirty minutes prior to the behavioral test, mice were injected IP with haloperidol (0.25 mg/kg) or physiological saline (10 ml/kg). Latencies of escape…
Chemical sympathectomy and clorgyline-induced stimulation of rat pineal melatonin synthesis
1989
The response to administration of the specific monoamine oxidase A (MAO-A) blocker clorgyline was investigated in adult male Sprague-Dawley rats which were sympathectomized by injection of the false neurotransmitter 6-hydroxydopamine as newborns. In intact animals which served as controls, the contents of pineal indoles melatonin, serotonin, 5-hydroxytryptophan were augmented, and the content of 5-hydroxyindoleacetic acid decreased 90 min following clorgyline injections when compared to saline receiving rats. Sympathectomized animals exhibited similar responses but these were less pronounced. It is suggested that blocking of the oxidation of both MAO-A substrates, noradrenaline and serotoni…
Probiotic mixture supplementation in the preventive management of trinitrobenzenesulfonic acid-induced inflammation in a murine model
2016
Inflammatory bowel diseases (IBD) are characterized by inflammatory conditions of the intestine. Probiotic bacteria (PB) can have beneficial effects in several gastrointestinal disorders. The objectives of this study were: (i) to provide an acute experimental IBD model induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS) in CD-1 mice, and (ii) to assess the preventive effects of Citogenex (Lactobacillus casei and Bifidobacterum lactis) supplementation on intestinal tissues and microbiota. Mice were inoculated intrarectally with saline, ethanol or different TNBS solutions. 1%TNBS induced clinical signs of colitis (P less than 0.01) and histological damage (P less than 0.01). Based on these r…
In Vivo Strain Analysis of Dilated Ascending Thoracic Aorta by ECG-Gated CT Angiographic Imaging
2017
Accurate assessment of aortic extensibility is a requisite first step for elucidating the pathophysiology of an ascending thoracic aortic aneurysm (ATAA). This study aimed to develop a framework for the in vivo evaluation of the full-field distribution of the aortic wall strain by imaging analysis of electrocardiographic- (ECG) gated thoracic data of 34 patients with ATAA. Seven healthy controls (i.e., non-aneurysmal aorta) from patients who underwent ECG-gated CT angiography for coronary artery diseases were included for comparison. To evaluate the systolic function, ECG-gated computed tomography (CT) angiography was used to generate patient-specific geometric meshes of the ascending aorta…
Effects of Calcium Antagonists on Rat Normal and Skinned Fundus
1992
Abstract Calcium chloride (CaCl2) (0·1−25 Mm, in K+-depolarized tissue), KCl (10−112 Mm) and acetylcholine (1 × 10−9 m−1 Mm) produced concentration-dependent contractions of rat isolated fundus. Verapamil (0·01−100 μm), cinnarizine (1−100 μm), trifluoperazine (10−500 μm) and dantrolene (50−250 μm) each produced a concentration-related rightward and downward shift of the log concentration-effect curve for CaCl2. The rank order of potencies of these antagonists, measured as the IC50 against Ca2+ (25 Mm)-induced contraction of depolarized fundus, was verapamil (2.5 μm) > cinnarizine (8·7 μm) > trifluoperazine (85·1 μm) > dantrolene (> 250 μm). Cinnarizine (0·5 Mm) a…
Distribution and induction of cytochrome P-450 and two cytochrome P-450-dependent monooxygenase activities in rat liver parenchymal cell subpopulatio…
1989
Liver parenchymal cells from the periportal and centrilobular zones differ in their morphological, biochemical and functional characteristics. In an effort to obtain fractions enriched in either periportal or centrilobular cells, isolated rat liver parenchymal cells were separated into five subpopulations by centrifugal elutriation. The mean diameters of the cells present in fractions I-V were 19.6, 21.1, 21.8, 22.7 and 23.5 micron, respectively. The content of cytochrome P-450 as well as benzphetamine N-demethylase and 7-ethoxyresorufin O-deethylase activities were higher in the larger parenchymal cells than in the smaller ones. After administration of phenobarbital the content of cytochro…