Various Organs Of Rat Research Articles

Alteration of the level of protein phosphatase 2C (IA) mRNA during the course of differentiation of skeletal muscle cells.

On Northern hybridization using the cDNA of type 2C protein phosphatase as a probe, substantial amount of the mRNA of type 2C protein phosphatase was detected in various organs of rats, suggesting that the type 2C protein phosphatase gene is a housekeeping gene. A relatively high level of the mRNA, however, was found in skeletal muscle compared with other organs. Similar results were obtained with the organs of mice. In addition, the mRNA level in C3H10T1/2 cells (embryonal mesenchymal cells of mice) was much lower than in mature skeletal muscle of mice. The mRNA level of type 2C protein phosphatase was enhanced in accordance with the differentiation of the C3H10T1/2 cells into myoblasts induced by the transfection of MyoD cDNA. These results suggest that type 2C protein phosphatase is related to the mechanism of differentiation of skeletal muscle cells.

Genotoxic effects of 2-amino-3,4-dimethylimidazo(4,5-f)quinoline (MeIQ) in rats measured by alkaline elution

The alkaline elution method was used to examine genotoxic effects of MeIQ in various organs of rats after in vivo exposure. No DNA damage could be observed in the stomach, small and large intestine, liver, kidney or testis of male Wistar rats 2 h after a single intraperitoneal dose of 80 mg/kg MeIQ. In rats that had been pretreated with Aroclor 1254 (PCB), MeIQ induced significant DNA damage in the liver after both oral and intraperitoneal injection. MeIQ induced DNA damage in the large intestine, liver and kidney of male F344 rats given a single intraperitoneal dose of 80 mg MeIQ/kg or fed 0.03% MeIQ for 13 days. The DNA damage did not seem to accumulate during the feeding period.

Similar effectsin vivo of two aluminum salts on the liver, kidney, bone, and brain ofRattus norvegicus

The widespread distribution of aluminum (Al) compounds in nature and their use have stimulated considerable interest in the toxicity of this metal. Aluminum accumulation has been suggested to be an associated phenomenon in various human diseases such as renal dialysis dementia, senile dementia, dialysis osteomalacia, microcytic hypochromic anaemia, gastrointestinal toxicity and Alzheimer's disease. The present work was undertaken to observe the effects of different concentrations of aluminum following oral ingestion for various durations on various organs of rats and also to compare two different Al salts at doses having the same amount of Al. The findings can be of relevance owing to the widespread use of aluminum compounds by oral route either as medicines or unintentionally through utensils and cookwares.

Cell free glutathione synthesizing activity of mercury resistant bacteria

Reduced glutathione (GSH) is present in all living cells and is known to have a generalized role in protecting the cells from heavy metal toxicity. Depletion of both GSH and glutathione reductase (GR) level upon treatment with mercuric chloride (HgCl{sub 2}) is reported in various organs of rat. However, the effect of HgCl{sub 2} on glutathione level in bacterial system is not known. In the present communication, the authors report the results of their investigation on the glutathione status in mercury resistant bacterial cells exposed to HgCl{sub 2}.

Modulation of glutathione in various organs of rat induced by acetaminophen

Modulation of glutathione in various organs of rat induced by acetaminophen

Immunohistochemical localization of 14 kDa ?-galactoside-binding lectin in various organs of rat

Immunohistochemical localization of 14 kDa beta-galactoside-binding lectin in various organs of adult rat was achieved using a monospecific antibody raised against lectin purified from rat lung. The antibody-stained cells were formed into small aggregates, thin fascicles, or thick bundles in the walls of blood vessels, gastrointestinal tracts and urogenital organs. From the patterns of distribution, as well as their organization, these immunoreactive cells were regarded as smooth muscle cells. This was confirmed by a double immunofluorescence study using a mixture of anti 14 kDa lectin and anti alpha-smooth muscle-specific actin antibodies. Strong 14 kDa lectin immunoreactivity was seen in the pericellular matrix of smooth muscle cells in intact organs as well as in detergent-treated organs from which all cellular components were extracted. From these findings, it is suggested that the 14 kDa lectin may be externalized by smooth muscle cells into their pericellular matrix and participate in the crosslinking of the complementary glycoconjugate(s) localized at that site. The macromolecular xomplex of glycoconjugates thus formed around smooth muscle cells may play a role in anchoring smooth muscle cells to the pericellular connective tissue thereby permitting the force of muscle contraction to be efficiently transmitted to the surrounding connective tissue proper.

A Study on the Pheripheral Anticholinergic Effect of Minaprine

The authors studied ED50 of bethanechol on the contractilities of the smooth muscles isolated from various organs of rat under the presence of atropine(a classical competitive blocker of cholinergic muscarinic receptor) or minaprine(a newly developed antidepressant drug) to investigate the pheripheral anticholinergic effect of minaprine. The results were as follows ; 1) There was no significant difference between ED50 of bethanechol in the control group and that under the presence of minaprine and in the smooth muscles isolated from the duodenum. 2) There was no significant difference between ED50 of bethanechol in the control group and that under the presence of minaprine and in the smooth muscles isolated from the ascending colon. 3) There was significant difference between ED50 of bethanechol in the control group and that under the presence of minaprine and in the smooth muscles isolated from the urinary bladder(P and minaprine () in the smooth muscles isolated from the urinary bladder(P

Distribution of vitamin A in various organs of rats in relation to the quality and the quantity of dietary proteins.

The influence of the quality and the quantity of dietary proteins on the distribution of a single massive dose of vitamin A in various organs of growing Wistar strain rats has been studied by using casein and bengal gram diets at 20% and 10% protein levels. The distribution of [3H]-retinyl acetate in various tissues was also investigated in these dietary conditions. The results show that the hepatic storage of dietary as well as a single massive dose (20,000 I.U.) of vitamin A was profoundly decreased in the rats fed on bengal gram diets as compared to those fed on casein diets. Regardless of hepatic stores, the plasma vitamin A levels were comparable in all the groups. Feeding of low quality of protein reduced the tissue distribution of [3H]-retinyl acetate in control as well as rats given a massive dose of vitamin A. This study suggests that both the poor quality and the inadequate quantity of dietary protein are detrimental influences on the vitamin A status of the growing rats.

Specific inhibitors for prolyl endopeptidase and their anti-amnesic effect.

Several peptides and peptide derivatives were tested for their inhibitory effect on prolyl endopeptidase and possible properties as anti-amnesic agents. Among the compounds tested, Z-Gly-Pro-CH2Cl, Z-Val-prolinal, Boc-Pro-prolinal, Z-Pro-prolinal, aniracetam and pramiracetam inhibited the enzyme activities at Ki values in the order of nM to microM, and the effect of the prolinal-containing peptide derivatives was specific for prolyl endopeptidase. Z-Pro-prolinal was the most effective inhibitor in vitro (Ki = 5 nM) and in vivo (50 to 70% inhibition in various organs of rat at a dose of 1 mumol/animal i.p.). Regional differences were observed in the effect of inhibitors on the brain enzyme activities: most active in mesencephalon, followed by striatum, cerebellum, hippocampus, hypothalamus; and inactive in cerebral cortex and medulla oblongata. In the passive avoidance learning test using rats, pretreatment with Z-Pro-prolinal prevented the induction of amnesia by scopolamine at the dose of 1 mumol/animal, i.p. Z-Val-prolinal, Z-Pyr-prolinal and Z-Gly-Pro-CH2Cl were also effective in the retention test at 24 and 48 h after the training trial. The antiamnesic effect of these compounds was approximately parallel to the in vitro inhibitory activities on prolyl endopeptidase. These results suggest the possibility that the inhibitors exhibit their anti-amnesic effect through the regulation of the enzyme activity in the brain.

ラットＣｕ，Ｚｎ‐ＳＯＤの精製と各臓器における免疫組織学的局在

Copper, zinc-superoxide dismutase (Cu, Zn-SOD) was purified from rat liver using Tsuchihashi fractionation, acetone treatment, ion exchange chromatography (DE-52, CM-52) . The purified enzyme showed 2bands in polyacrylamide gel electrophoresis (PAGE), but in SDS-PAGE and isoelectric focusing showed a single band (M.W. 16, 000, pH 5.1) . It was found that Cu, Zn-SOD had electrophoretic variants and there was no immunological difference among the variants.Immunolocalization in various organs of rat was investigated using antiserum against Cu, Zn-SOD. Localization in rat organs was almost the same as that in human, previously reported.Cu, Zn-SOD was seen in the cells which function was related to the transport of electrocyte and water in the cases of parietal cells, duct epithelium of salivary gland and pancreas, intrahepatic biliary duct, epithelium of intestine, distal convoluted tubles and Henle's loops.Futhermore, localization of the islets of Langerhans and the medulla in adrenal gland may show that superoxide radical plays a role in the function of the endocrine cells.On the other hand, localization in the SOD positive cells was found in the cytoplasm and partially in the nucleus. SOD in the nucleus may protect the nucleic acid from the damage by superoxide radical.In conclusion, superoxide radical and SOD plays an important role in various organs.

Lactic dehydrogenase activity in various organs of rats fed cottonseed flour

Male rats fed cottonseed meal diet or protein-free diet for four weeks showed a decreased lactic dehydrogenase (LDH) activity in the liver, heart and testicle, but not in skeletal muscle. At the end of this treatment, the animals were fed with Purina Chow control diet for 14 weeks of recovery. After ten weeks of recovery, the animals fed cottonseed meal showed normal LDH values for the testicle and heart. In the liver, the low value remained so during the 14 weeks of recovery. Normal values were reached in the animals fed protein-free diet at six weeks of recovery. The decreased LDH activity in animals fed cottonseed diet may be due to the gossypol present in it.

Use of monoclonal and polyclonal antibodies against DNA adducts for the detection of DNA lesions in isolated DNA and in single cells.

Interaction of genotoxic chemicals with their intracellular target, i.e., DNA, may result in the formation of covalent adducts. Various methods have been developed to estimate exposure to genotoxic chemicals by means of molecular dosimetry of DNA adducts. Such experiments have generally been carried out with radiolabeled genotoxicants administered in vitro to cultured cells or in vivo to laboratory animals. Biomonitoring of human exposure to genotoxic chemicals requires methods to detect very small quantities of nonradioactive DNA adducts in limited amounts of sample. Attention has been devoted to the development of immunochemical techniques in which specific DNA adducts can be detected with antibodies. The level of sensitivity achieved in these experiments renders these methods applicable for human biomonitoring. When suitable antibodies are available, the immunochemical approach enables one to analyze various types of adducts separately, and to discriminate between irrelevant (e.g., quickly repairable) and relevant lesions (key lesions) with respect to biological end points such as mutation induction and cancer. Polyclonal and monoclonal antibodies were used for the detection of DNA adducts in animal and human tissue. Adducts were measured in DNA from various organs of rats treated with the liver carcinogen 2-AAF. Human exposure to genotoxic agents was studied by the measurement of DNA adducts in blood cells from patients treated with the genotoxic cytostatic cisplatin. Also, the development is described of a system to detect and quantitate DNA adducts at the single-cell level by means of immunofluorescence microscopy, which allows the analysis of small samples of human tissue with preservation of cell morphology.

The organ-specific induction of DNA adducts in 2-acetylaminofluorene-treated rats, studied by means of a sensitive immunochemical method

Exposure of cells to chemical carcinogens and mutagens may result in the formation of DNA adducts, which can give rise to mutations in the genome and to cellular transformation. Methods to measure DNA-adduct formation may be useful for ‘biomonitoring’, to establish exposure of laboratory animals or humans to DNA-damaging agents. For such purposes, immunochemical methods appear to be suitable, because they allow sensitive detection and quantification of DNA adducts in small amounts of sample in a non-radiolabelled form. We have worked out optimal conditions for the detection of DNA adducts by means of competitive enzyme-linked immunosorbent assay (ELISA). This technique involves interaction of soluble antigen, immobilized antigen and antibody. It appeared that the sensitivity of the competitive assay can be improved by lowering the amount of immobilized antigen, adsorbed to the wall of the plastic reaction vessel. On the basis of these observations, suitable conditions were selected for a sensitive quantitative assay of adducts in DNA isolated from various organs of rats, treated (p.o.) with the liver carcinogen 2-acetylaminofluorene (2-AAF). Under the conditions of these experiments, the available rabbit antiserum recognizes the guanosine-AAF adduct with high specificity. A time- and dose-dependent induction of AAF adducts could be measured in liver DNA from exposed rats, whereas the amount of adducts in DNA from spleen and nucleated blood cells remained below the detection limit (1 adduct/10 8 nucleotides). The implications of these findings with respect to the relevance of blood cell biomonitoring for target cell exposure are discussed.

1,7-Diethylguanosine formation in tRNA chemical ethylation by ethionine and ethylnitrosourea

The mechanism of ethionine carcinogenesis and more generally the relationship between alkylation of nucleic acids by chemical carcinogens and oncogenesis still remain obscure. In the present study the rat liver tRNA ethylation by L-[ ethyl-1- 3H]ethionine was reinvestigated by examining in particular the highly radioactive ‘pyrimidine-nucleotide-like’ fraction found earlier in acid hydrolysates of hepatic tRNA from ethionine-treated rats. The following results were obtained: (1) ultraviolet-spectral and chromatographic analyses showed the presence of 1,7-diethylguanosine in this ‘pyrimidine-nucleotide-like’ fraction; (2) the dialkyl compound was recovered exclusively in the form of imidazole-ring-opened derivatives. When [1- 14C]ethylnitrosourea was used as alkylating agent, the in vivo ethylation pattern of tRNA from various organs of rat showed an analogous radioactive ‘pyrimidine-nucleotide-like’ fraction as main radiactive product. On the contrary, tRNA ethylation pattern after in vitro reaction with [1- 14C]ethylnitrosourea exhibited a main radioactivity peak (85% of the total radioactivity recovered) in coincidence of the chromatographic area of 1,7-diethylguanine. The 1,7-diethylguanosine moieties of tRNA were extremely labile both under physiological and alkaline conditions. The 1,7-diethylguanine-associated radioactivity was completely lost from [ 14C]ethyl-tRNA after only 7 h incubation at 37°C and pH 7.3, while at pH 11.4 this process was preceded by the conversion of the 1,7-diethylguanosine residues into imidazole-ring-opened derivatives.

Instrumental neutron activation analysis in study of the toxicity of trialkyltin-methacrylic copolymer as an antifouling agent

The analysis of tin in biological materials is rarely reported. In this study, instrumental neutron activation analysis was used to determine the tin together with some other trace elements in various organs of rats treated with trialkyltin-methacrylic copolymer. No appreciable accumulation of tin and variation of distribution of trace elements (Cr, Fe, Zn and Co) in various organs are found. The pathological changes in the liver sections cannot be observed either. This therefore indicates that the toxicity of trialkyltin-methacrylic copolymer is low, if any.

Formation of m-tyrosine and o-tyrosine from L-phenylalanine in various tissues of rats.

The hydroxylation of L-phenylalanine was investigated in subcellular fractions of various organs of rat under aerobic conditions. L-Phenylalanine was metabolized to p-, m-, and o-tyrosine in the 2000×g homogenates of liver, kidney, brain and adrenal of male rats. The three metabolites in the incubation mixture were determined by high-performance liquid chromatography. This hydroxylation reaction occurred only in the postmicrosomal fraction of the organs mentioned above but not in the microsomal fractions, and required a pteridine as a cofactor. The hydroxylation of phenylalanine was inhibited by the addition of p-chlorophenylalanine and α-methyltyrosine, which are specific inhibitors of phenylalanine hydroxylase and tyrosine hydroxylase, respectively. On the other hand, superoxide dismutase and potassium iodide, which are known scavengers of the superoxide radical and hydroxyl radical, had no significant effect on the hydroxylation. These results indicate that the hydroxylation of phenylalanine to m- and o-tyrosines is caused mainly by phenylalanine hydroxylase and tyrosine hydroxylase.

Formation and metabolism of pungent principle of Capsicum fruits. Part XIV. In vivo and in vitro metabolism of dihydrocapsaicin, a pungent principle of hot pepper, in rats.

The metabolism in rats of dihydrocapsaicin, a pungent principle of hot pepper, was investigated in vivo and in vitro by thin-layer chromatography, high-performance liquid chromatography and combined gas chromatography-mass spectrometry. Within 48 hr of oral administration of dihydrocapsaicin (20 mg/kg body weight) to male adult rats, unchanged dihydrocapsaicin and eight of its metabolites were identified in urine; i.e., dihydrocapsaicin (8.7% of total dose), vanillylamine (4.7%), vanillin (4.6%), vanillyl alcohol (37.6%) and vanillic acid (19.2%) as free forms and/or their glucuronides. The proportions of free and glucuronide metabolites in urine were 14.5% and 60.5% of the total dose. Part of the unchanged dihydrocapsaicin (10% of total dose) was excreted into the feces within 48 hr. Cell-free extracts of rat liver catalyzed the hydrolysis of dihydrocapsaicin to vanillylamine and 8-methyl nonanoic acid. The former compound was further transformed to vanillin in situ. Dihydrocapsaicin-hydrolyzing enzyme activity was found in various organs of rat. The activity was located mainly in the liver. On the basis of the present data, the metabolic pathway of dihydrocapsaicin in rats was proposed.

Effect of inhalation of coal fly ash on vitamin A distribution in organs of the rat.

Fly ash contains several polycyclic aromatic hydrocarbons. The effect of inhalation of coal fly ash on vitamin A distribution in various organs of rat has been studied. Inhalation of fly ash for 6 h daily, for 15 d, decreased vitamin A content in liver. The absorption of orally given [3H]retinyl acetate was decreased and so was its localization in liver of rats inhaling coal fly ash.

Experimental infection in newborn mice and rats by hemorrhagic fever with renal syndrome (HFRS) virus.

Newborn mice and rats were inoculated intracerebrally (ic) or intraperitoneally (ip) with Hantaan virus (76-118 strain) or HFRS-related virus (B-1 strain). The mortality and the influence on the increase of body weight in newborn mice were higher in the groups infected with the 76-118 strain than in the groups infected with the B-1 strain, while the B-1 strain was more virulent in rats than the 76-118 strain. Virus isolation from rats inoculated with either strain was attempted 7 and 11 weeks after inoculation. Virus could be isolated from various organs of rats infected with the B-1 strain, while it was recovered from only the brain and lungs of rats infected with the 76-118 strain. Viral antigen was readily detected in various organs of rats infected with the B-1 strain, but the amount and distribution of antigens were less in rats infected with the 76-118 strain. Our results suggest that the virulence of HFRS-related virus is variable, depending on the species of infected animals as well as on the virus strains. The virus also persists in the injected animals with high titers of antibodies for at least 11 weeks.

Inhibition of compound 48/80--induced vascular protein leakage by pretreatment with capsaicin and a substance P antagonist.

Intravenous injection of compound 48/80 (1 mg X kg-1) induced an acute increase in vascular permeability to plasma proteins in various organs of rats. The compound 48/80 response was partly inhibited by histamine H1 and H2 receptor blockade in the urinary bladder and in the duodenum, but not in the trachea, the oesophagus, the ureter and the paw skin. Blockade of 5-hydroxytryptamine receptors with methysergide led to a reduction of the permeability response in the oesophagus and in the urinary bladder, leaving responses in other organs unchanged. Pretreatment of neonatal rats with capsaicin almost abolished the 48/80 response in all organs except in the duodenum. Pretreatment of rats with [D-Arg1, D-Trp7,9, Leu11]-substance P, a substance P antagonist, also caused a partial inhibition of the permeability response to compound 48/80 in several organs. Topical administration of compound 48/80 (1 mg X ml-1) onto the tracheal mucosa induced local Evans blue extravasation. This response was resistant to pretreatment with histamine receptor antagonists, but was largely inhibited after neonatal capsaicin pretreatment. Topical administration of compound 48/80 (1 mg X ml-1 or 10 mg X ml-1) into the eye did not cause visible Evans blue extravasation in the conjunctiva, nor any signs of pain reaction as indicated by the absence of the wiping response, usually seen upon noxious chemical stimuli in the eye. In guinea-pigs, 10 mg X kg-1 compound 48/80 i.v. were required to induce vascular protein leakage in different organs. This response was blocked by pretreatment with H1 and H2 receptor antagonists, but only slightly reduced after systemic capsaicin pretreatment of guinea-pigs.(ABSTRACT TRUNCATED AT 250 WORDS)