Various Tissues Of Rat Research Articles

白蟻防除処理剤クロルデンの公衆衛生学的研究

I exposed rats to chlordane (industrial product) and measured the concentration of chlordane in various tissues of rats over time. Exposure to chlordane for 3.5 hours appoximated the exposure to chlordane in a house a hundred days after treatment for termites. However, chlordane and metabolites were detected in all the tissues of rats. The concentration of chlordane in various tissues showed highest level one hour after exposure. After that, heptachlor, γ-chlordane, trans-chlordane and cis-chlordane were excreted fast, while trans-noachlor and cis-nonachlor were excreted extremely slowly. The metabolites of chlordane (heptachlorepoxide and oxichlordane) showed the highest level one after exposure in the various tissues, and after that they were excreted slowly. Chlordane had the highest level in the adipose tissue and the second highest level in the liver, kidney, lung, pectoral muscle and heart. In the spleen and brain it showed a relatively low level. The lowest level was in the blood. As for Biological Harf Life (B. H. L.), the number of days in the secondary excretion in the adipose tissue of chlordane excreted late was as follows: trans-nonachlor 38.5 days, cis-nonachlor 16.5 days, and metabolites 16.9 days. It is suggested that the chronic toxicity of trans-nonachlor, cis-nonachlor and metabolites should be investigated in future.

Recovery from amiodarone-induced lipidosis in laboratory animals: A toxicological study

Numerous amphiphilic cationic drugs cause lipid-lysosomal storage in animal tissues; one of these drugs is amiodarone, a major antiarrhythmic agent. The toxicological effects of amiodarone were studied in three animal species (rats, dogs, and monkeys). It was shown that sublethal dose levels of amiodarone induced lipid storage in a great variety of tissues in rats (Fischer and Sprague-Dawley strains) and dogs. However, this change was not observed in baboons and Wistar rats. This storage, essentially characterized by lamellated inclusions, affected foamy macrophages, and at a later phase multiple cell types. Tissue biochemical analysis provided evidence of the phospholipidic nature of the storage. In addition, amiodarone induced an increased cholesterolemia and marked modifications of the lipoproteinogram. The kinetics of lipid storage was demonstrated following oral administration of amiodarone. After jejunal absorption, lipid storage occurred in the mesenteric lymph nodes followed by widespread deposition in the other lymph nodes and tissues, particularly in the lung. A complete recovery from lipid storage was observed in dogs and rats. Finally, an investigation of a correlation between animal and man by means of long-term experiments is proposed.

Two species of chromatin-RNA polymerase II complex are commonly present in nuclei of various tissues of rats.

When rat liver nuclei were digested with nuclease, we found that the chromatin-bound RNA polymerase II was liberated as two distinct complexes, peak 1 and peak 2, which seemed to reflect different functional states in cell nuclei. We further examined their occurrence in nuclear digests of various tissues of rats and the following results were obtained. Upon digestion with micrococcal nuclease of nuclei from brain, spleen, testis and kidney, chromatin-bound RNA polymerase II was liberated as two distinct forms which sedimented differently in a sucrose density gradient. The sedimentation rate of peak 1 varied depending on the tissue nuclei examined. After high salt or RNase treatment of the nuclear digests, peak 1 from liver, brain, spleen and testis nuclei showed the same sedimentation rate as did kidney peak 1, the rate for which remained unchanged by these treatments. The results suggested that peak 1 complexes from various tissue nuclei had basically the same structural organization, and we confirmed this by electrophoretic studies on RNase-treated liver and kidney nuclear digests. Peak 2 from various tissue nuclei exhibited identical sedimentation rates. Thus, the chromatin-bound RNA polymerase II seems to exist commonly in two distinct states in cell nuclei of rats.

Determination of imidazole acetic acid and its conjugate(s) levels in urine, serum and tissues of rats: studies on changes in their levels under various conditions

A convenient and reproducible method for assay of imidazole acetic acid (ImAA) was developed as a modification of that described previously (Watanabe et al., 1983). ImAA conjugate(s) (ImAA-C), mainly consisting of imidazole acetic acid riboside, could be measured by this method after its hydrolysis to ImAA. The ImAA and ImAA-C levels in various tissues of rats were measured and the effects of various agents on these levels were studied. The renal clearance values of ImAA-C in rats and man were similar to the creatinine clearance values, but those of ImAA were 1/40 of those of ImAA-C, suggesting that the latter is readily excreted in the urine. Consistent with this idea, the urinary excretion of ImAA-C was found to increase much more than that of other histamine metabolites during late pregnancy, when the foetus produces much histamine.

A rapid high-performance liquid chromatographic procedure for the simultaneous determination of methionine, ethionine, S-adenosylmethionine, S-adenosylethionine, and the natural polyamines in rat tissues

A method for the analysis of S-adenosyl- l-methionine (SAM) and S-adenosyl- l-ethionine (SAE) and their major metabolites by high-performance liquid chromatography is described. The procedure allows the simultaneous analysis of the natural polyamines, putrescine, spermidine, and spermine, and some of the major amino acids, methionine, tyrosine, and tryptophan. The uv absorbance at 254 nm is used for the determination of the SAM and SAE analogs, whereas the polyamines and amino acids are analyzed by fluorescence detection after postcolumn derivatization with o-phthalaldehyde. The method allows SAM and polyamine determinations by direct injection of the tissue extracts without prepurification. The procedure is applied to study the effects of dl-ethionine treatment on the SAM, SAE, methionine, and polyamine levels in various tissues of rats.

Differential expression of two neural cell-specific beta-tubulin mRNAs during rat brain development.

We recently demonstrated that beta-tubulin mRNA expression is regulated during rat brain development. This is manifested by a dramatic decrease in both 1.8- and 2.9-kilobase (kb) mRNAs when extensive neurite elongation is occurring. Coincident with these decreases is the increased production of a 2.5-kb mRNA. (J.F. Bond and S.R. Farmer, Mol. Cell. Biol. 3:1333-1342, 1983). In the present study, we have isolated and characterized three different cDNAs corresponding to beta-tubulin mRNAs (R beta T.1, R beta T.2, and R beta T.3). Hybridization of 3' untranslated region subclones of R beta T.1 and R beta T.2 cDNAs to RNA from a variety of rat tissues and cells revealed that these two cDNAs are neural cell specific. R beta T.1 corresponds to an abundant 1.8-kb mRNA expressed only at early stages of rat brain development. R beta T.2 corresponds to the 2.5-kb mRNA expressed at later stages. These data strongly suggest that there is differential expression of the beta-tubulin multigene family during rat brain development.

Differential expression of two neural cell-specific beta-tubulin mRNAs during rat brain development.

We recently demonstrated that beta-tubulin mRNA expression is regulated during rat brain development. This is manifested by a dramatic decrease in both 1.8- and 2.9-kilobase (kb) mRNAs when extensive neurite elongation is occurring. Coincident with these decreases is the increased production of a 2.5-kb mRNA. (J.F. Bond and S.R. Farmer, Mol. Cell. Biol. 3:1333-1342, 1983). In the present study, we have isolated and characterized three different cDNAs corresponding to beta-tubulin mRNAs (R beta T.1, R beta T.2, and R beta T.3). Hybridization of 3' untranslated region subclones of R beta T.1 and R beta T.2 cDNAs to RNA from a variety of rat tissues and cells revealed that these two cDNAs are neural cell specific. R beta T.1 corresponds to an abundant 1.8-kb mRNA expressed only at early stages of rat brain development. R beta T.2 corresponds to the 2.5-kb mRNA expressed at later stages. These data strongly suggest that there is differential expression of the beta-tubulin multigene family during rat brain development.

Cyclosporine inhibits prolactin induction of ornithine decarboxylase in rat tissues

Cyclosporine (CyA), formerly cyclosporin A, significantly inhibited the ability of prolactin (PRL) to elevate ornithine decarboxylase (ODC) activity in a variety of rat tissues. Administration of PRL to hypophysectomized rats also resulted in an induction of ODC activity which was inhibited markedly in all tissues studied in the presence of CyA. Transglutaminase (TGase) activity was not affected in any significant manner by PRL or CyA in most tissues studied. However, it was elevated in the adrenal by 10 −8 M PRL. Bromocryptine, which selectively antagonizes pituitary PRL release, decreased the kidney ODC basal levels to 30% of vehicle control and serum PRL level to 4.3 ± 1.4 compared to 28 ± 10 in controls, suggestive of PRL maintenance of steady-state ODC activity in the kidney. CyA administration did not affect the action of glucagon, a known cyclic AMP-mediated hormone, or 8-bromo-cyclic AMP on kidney ODC activity. The elevation of rat kidney ODC activity by dexamethasone and triiodothyronine (T 3), compounds which elevated serum prolactin levels in all cases, was also blocked by administration of CyA. Epidermal growth factor (EGF), which did not induce rat kidney ODC activity by itself, was capable of producing a small increment in ODC activity in the presence of CyA. The marked effect of CyA to selectively block ODC induction by PRL may be due to the ability of CyA to interact with receptor-required phospholipids in membranes and thus to antagonize hormone-receptor interaction.

High-performance liquid chromatographic analysis of S-adenosylmethionine and its metabolites in rat tissues: interrelationship with changes in biogenic catechol levels following treatment with l-DOPA

A metho is described for the simultaneous analysis of S-adenosylmethionine (SAM) and its metabolites, S-adenosylhomocysteine (SAH) and decarboxylated S-adenosylmethionine along with the neutral polyamines, putrescine, spermidine and spermine. The separation is obtained by a reversed-phase ion-pair liquid chromatographic procedure with gradient elution folloed by dual detection. The UV absorbance at 254 nm is used for the analysis of SAM and of the SAM metabolites, whereas the polyamines and some major amino acids, e.g., methionine, tyrosine and tryptophan, are analyzed by fluorescence detection after UV-cell derivatization with o-phthalaldehyde. A separate ion-pair reversed-phase high-performance liquid chromatographic (HPLC) procedure using isocratic elution and electrochemical detection is employed to analyse in the same tissue extracts the catechols and 5-hydrxyindoles, 3,4-dihydroxyphenylalanine (DOPA), dopamine, norepinephrine, 3,4-dihydroxyphenylacetic acid, homovanillic acid, 4-hydroxy-3-methoxyphenylalanine, tryptophan, 5-hydroxytryptophan, serotonin and 5-hydroxyindolacetic acid. The sample preparation for the two HPLC procedures requires only homogenization of the tissues in perchloric acid and centrifugation before injection onto the column. The two chromatographic procedures have been applied to study the interrelationship, in various tissues of rats, between the SAM and SAH levels and the biogenic catechols after different treatments with l-DOPA alone or in combination with α-monofluoromethyl-DOPA, a potent enzyme-activated irreversible inhibitor of aromatic l-amino acid decarboxylase.

The determination of zirconium in biological materials by photon activation analysis

Non-destructive photon activation analysis with 30-MeV bremsstrahlung has been applied for the determination of zirconium in biological materials. The materials investigated were the NBS SRMs Orchard Leaves and Bovine Liver, and various tissues of rats. The detection limits of this method for a 2 h irradiation are 0.1 μg for Orchard Leaves, 0.04 μg for Bovine Liver and animal tissues. The zirconium contents of animal tissues obtained in this work appear to be significantly lower than the values reported earlier. New data on zirconium in the NBS SRMs are presented.

Determination of cystamine by high-performance liquid chromatography

A highly sensitive and specific assay method for cystamine using high-performance liquid chromatography has been developed. The method is based on postcolumn derivatization of cystamine with o-phtalaldehyde in the presence of 2-mercaptoethanol and sodium hypochlorite. The separation of cystamine was achieved using a cation exchange column ( ISC-05 S0504 ). The assay was linear over the concentration range of 2 to 200 pmol. For the application of this assay method to biological materials, the pretreatment with a cation exchange column (Dowex 50W×8) was necessary to remove interfering o-phthalaldehyde-reactive substances. Since cysteamine in biological materials was quantitatively converted to cystamine during these sampling procedures, this method was found to be suitable for assaying the cysteamine plus cystamine content in various organs and tissues. The cysteamine-cystamine content in various tissues of rat determined by the present assay method has been presented.

Gangliosides of various rat tissues: distribution of ganglio-N-tetraose-containing gangliosides and tissue-characteristic composition of gangliosides.

Gangliosides were extracted from various tissues of rat (Wistar strain, male, 3 months old) and their structures were elucidated by enzymatic and chemical procedures including the analysis by negative ion fast atom bombardment mass spectrometry. All tissues analyzed contained gangliosides in various but characteristic concentrations. GD1a was detected in the various extraneural tissues (erythrocytes, buffy coat, bone marrow, testis, spleen, and liver) in amounts corresponding to more than 30% of total lipid-bound sialic acid, and surprisingly, it was the sole ganglioside found in buffy coat. The extraneural tissues were classified into several categories according to the nature of the asialo-oligosaccharides of gangliosides as follows: (1) gangliosides with ganglio-N-tetraose were exclusively present (buffy coat and erythrocytes), (2) the concentration of ganglio-N-tetraose-containing gangliosides was higher than that of lactose-containing gangliosides (testis and bone marrow), (3) ganglio-N-tetraose-containing gangliosides amounted to 25-30% of lactose-containing gangliosides (liver and spleen), (4) ganglio-N-tetraose-containing gangliosides amounted to 7-11% of lactose-containing gangliosides (lung and stomach), (5) more than 90% of gangliosides were lactose-containing gangliosides (heart, intestine, and kidney). In addition, the following gangliosides were characteristically detected in high concentration in the following tissues: GM4 in kidney. GM2 in bone marrow, fucosyl GM1 and GM1 in erythrocytes and GM3 with 2-hydroxy fatty acid, phytosphingosine and N-glycolylneuraminic acid in intestine.

Metabolism of potassium bromate in rats II. In vitro studies

To learn more about the biodegradation of potassium bromate, the decomposition of bromate in various tissues of rats was studied. Bromate was degraded very slowly in human saliva and plasma of rat. However, nearly all tissue homogenates and red blood cells could degrade bromate by a mechanism which exhibited some stability to heat. Furthermore, it was suggested that the bromate degradation active component in the supernatant fraction of a liver homogenate was in part glutathione.

Nuclear protein kinases.

Nuclear protein kinases include enzymes that transfer the gamma-phosphate of ATP to serine, threonine, lysine or histidine in proteins. Nuclear kinases with a preference for basic proteins are known as histone kinases; those preferring acidic protein substrates are casein kinases. Histone kinases include both cyclic AMP-independent protein kinases and cyclic AMP-dependent protein kinases. The best-characterized cyclic AMP-independent nuclear protein kinase is associated with cell proliferation and is activated (or transported to the nucleus) in G2 phase of the cell cycle. It phosphorylates specific serine and threonine residues in the non globular domains of histone H1 and appears to promote chromosome condensation. The cyclic AMP-dependent protein kinase has unknown nuclear function(s), although it may be translocated from cytoplasm to nucleus in response to specific hormonal stimuli which are also associated with changes in transcriptional activity. There is a massive peak of nuclear cyclic AMP-dependent protein kinase activity in G2 phase of the cell cycle. Nuclear casein kinases are apparently very heterogeneous. Two of these enzymes have been purified to homogeneity. They phosphorylate non-histone chromosomal proteins, including RNA polymerase and ornithine decarboxylase. Phosphorylated ornithine decarboxylase is inactive enzymatically but, in Physarum, it binds to the rDNA minichromosome and stimulates rRNA transcription. Kinases forming phosphoramidate bonds occur in a variety of rat tissues and form phosphohistide in histone H4 and phospholysine in histone H1.

Evidence that the hypothalamus may be a source of a circulating Na+-K+-ATPase inhibitor.

Acetone extracts from a variety of rat tissues were tested for their ability to stimulate renal glucose-6-phosphate dehydrogenase (G6PD) activity at 2 min in an in-vitro cytochemical assay which is a marker of the sodium potassium-dependent adenosine triphosphatase (Na+-K+-ATPase) inhibiting activity. Extracts of the hypothalamus were the only ones found to be active in this system. Acetone extract of hypothalamus also inhibited renal Na+-K+-ATPase activity in vitro. The G6PD-stimulating activity from one hypothalamus was about 10000 to 100000 times greater than that of 1 ml plasma. The G6PD-stimulating activity of hypothalamic extracts from rats which had been on a high sodium intake for 4 weeks were approximately 150 times more active than those obtained from rats which had been on a low sodium diet. The G6PD-stimulating activity of the corresponding plasma was sixfold more active. These findings suggest that a circulating sodium transport inhibitor(s) may be secreted from the hypothalamus.

Carcinogenesis and aging. II. Modifying effect of aging on metabolism of methyl(acetoxymethyl)nitrosamine and its interaction with DNA of various tissues in rats.

Young (3 month-old) and old (14 month-old) female outbred rats received a single i.p. dose (13 mg/kg) of N-[14C]methyl-Nacetoxymethylnitrosamine [( 14C]DMN-OAc), which, under these conditions, selectively induces intestinal tumours. Complete DMN-OAc breakdown occurred within 30 min in both young and old rats but exhalation of 14CO2 continued for over 1 h in young rats and over 3 h in old rats. The highest level of methylation in both young and old rats was found in the DNA of epithelial cells of the colon and in other adjacent abdominal organs (liver and uterus). The initial capacity for excision of the O6-methylguanine from liver DNA was greater in young animals, but further this DNA adduct was repaired more efficiently by the liver of old rats. In the DNA of ileal and colonic enterocytes, O6-methylguanine excision was higher in young than in old animals. The DNA tertiary structure, measured by the sedimentation pattern of nucleoids in neutral sucrose gradient, was damaged in old rats, and, to a lesser extent, in young rats. The non-uniform pattern of DNA damage in young and old animals may be associated with differing carcinogenic effects of DMN-OAc in rats of different ages, a hypothesis which is currently under test.

The Induced Synthesis of Metallothionein in Various Tissues of Rat after Injection of Various Metals

The Induced Synthesis of Metallothionein in Various Tissues of Rat after Injection of Various Metals

Microautoradiographic study on the tissue localization of liposome-entrapped or unentrapped 3H-labeled .BETA.-galactosidase injected into rats.

The localization of intravenously injected liposome-entrapped or unentrapped 3H- beta-ga lactosidase in various tissues of rats was investigated by microautoradiography. The microautoradiographic silver grains, indicating the uptake of both forms of the enzyme were observed in all of the rat tissues studied, such as the liver, kidneys, spleen, lungs, heart, muscle and brain. The liver was found to be the most active in taking up both forms of the enzyme and probably Kupffer cells were primarily involved in the uptake of the enzyme. Also in the brain, the uptake of both forms of the enzyme was observed, though far less extensively, through the blood-brain barrier. The uptake of the enzyme in the brain was somewhat greater in the gray matter than in the white matter.

Distribution of met 5-enkephalin-Arg 6-Phe 7 (MEAP) in various tissues of rats and guinea pigs

With a specific and sensitive radioimunoassay coupled to HPLC separation, we have measured met 5-enkephalin-Arg 6-Phe 7 in extracts of various peripheral organs. The highest content was found in ileum and lung. The MEAP in lung can be released in Ca ++-dependent manner by KCl. The ratio of MEAP/ME seems to differ in various peripheral tissues, suggesting that MEAP may not only be a precursor of ME but may also act as a neurotransmitter or neuromodulator itself.

Sequence content of α-fetoprotein, albumin and fibrinogen polypeptide mRNAs in different organs, developing tissues and in liver during carcinogenesis in rats

To investigate the variable gene activities of α-fetoprotein, albumin and fibrinogen polypeptides as markers of ‘liver specific proteins’ in different developing organs or tissues, we have used specific complementary DNA probes to detect and to quantitate α-fetoprotein, albumin and fibrinogen polypeptide mRNA, respectively, in RNA fractions, prepared from various tissues of rats at different stages of fetal and postnatal development and from hepatomas induced by diethylnitrosamine. The results indicate that there is no consistent relationship between sequence content of α-fetoprotein, albumin and fibrinogen polypeptide mRNA in different developing tissues. Intestines which are like the liver also of endodermal origin do not contain α-fetoprotein, albumin and fibrinogen polypeptide mRNAs, while kidneys which are mesodermal in origin were found to be α-fetoprotein, albumin and fibrinogen polypeptide mRNA producers in neonatal life. In yolk sac, only α-fetoprotein and fibrinogen polypeptide mRNA could be detected. In the liver, the increased level of albumin and fibrinogen polypeptide mRNA during fetal and neonatal development is accompanied with a diminished amount of α-fetoprotein mRNA. The neosynthesis of α-fetoprotein mRNA in the liver during carcinogenesis occurred without a decreased content of albumin and fibrinogen polypeptide mRNAs. These findings suggest that complex mechanisms of gene regulation are involved in variable gene activities of α-fetoprotein, albumin and fibrinogen polypeptides in cells of different organs or tissues developed from a single cell.