Search

BACKGROUND: Chronic alcohol exposure can alter glucocorticoid receptor (GR) function in some brain areas that promotes escalated and compulsive-like alcohol intake. GR antagonism can prevent dependence-induced escalation in drinking, but very little is known about the role of GR in regulating high-risk non-dependent alcohol intake. Here, we investigate the role of GR in regulating binge-like drinking and aversive responses to alcohol in the High Drinking in the Dark (HDID-1) mice, which have been selectively bred for high blood ethanol concentrations (BECs) in the Drinking in the Dark (DID) test, and in their founder line, the HS/NPT. METHODS: In separate experiments, male and female HDID-1 mice were administered one of several compounds that inhibited GR or its negative regulator, FKBP51 (mifepristone [12.5, 25, 50, 100 mg/kg], CORT113176 [20, 40, 80 mg/kg], and SAFit2 [10, 20, 40 mg/kg]) during a 2-day DID task. Ethanol consumption and BECs were measured. Ethanol conditioned taste and place aversion (CTA and CPA, respectively) were measured in separate HDID-1 mice after mifepristone administration to assess GR’s role in regulating the conditioned aversive effects of ethanol. Lastly, HS/NPT mice were administered CORT113176 during DID to assess whether dissimilar effects from those of HDID-1 would be observed, which could suggest that selective breeding had altered sensitivity to the effects of GR antagonism on binge-like drinking. RESULTS: GR antagonism (with both mifepristone and CORT113176) selectively reduced binge-like ethanol intake and BECs in the HDID-1 mice, while inhibition of FKBP51 did not alter intake or BECs. In contrast, GR antagonism had no effect on ethanol intake or BECs in the HS/NPT mice. Although HDID-1 mice exhibit attenuated ethanol CTA, mifepristone administration did not enhance the aversive effects of ethanol in either a CTA or CPA task. CONCLUSION: These data suggest that the selection process increased sensitivity to GR antagonism on ethanol intake in the HDID-1 mice, and support a role for the GR as a genetic risk factor for high-risk alcohol intake.

We have modelled genetic risk for binge-like drinking by selectively breeding High Drinking in the Dark-1 and −2 (HDID-1 and HDID-2) mice for their propensity to reach intoxicating blood alcohol levels (BALs) after binge-like drinking in a single bottle, limited access paradigm. Interestingly, in standard two-bottle choice (2BC) tests for continuously available alcohol versus water, HDID mice show modest levels of preference. This indicates some degree of independence of the genetic contributions to risk for binge-like and sustained, continuous access drinking. We had few data where the drinking in the dark (DID) tests of binge-like drinking had been repeatedly performed, so we serially offered multiple DID tests to see whether binge-like drinking escalated. It did not. We also asked whether HDID mice would escalate their voluntary intake with prolonged exposure to alcohol 2BC. They did not. Lastly, we assessed whether an alcohol deprivation effect (ADE) developed. ADE is a temporary elevation in drinking typically observed after a period of abstinence from sustained access to alcohol choice. With repetition, these periods of ADE sometimes have led to more sustained elevations in drinking. We therefore asked whether repeated ADE episodes would elevate choice drinking in HDID mice. They did not. After nearly 500 days of alcohol access, the intake of HDID mice remained stable. We conclude that a genetically-enhanced high risk for binge-like drinking is not sufficient to yield alterations in long-term alcohol intake.

Two independent lines of High Drinking in the Dark (HDID-1, HDID-2) mice have been bred to reach high blood alcohol levels after a short period of binge-like ethanol drinking. Male mice of both lines were shown to have reduced sensitivity to develop a taste aversion to a novel flavor conditioned by ethanol injections as compared with their unselected HS/NPT founder stock. We have subsequently developed inbred variants of each line. The current experiments established that reduced ethanol-conditioned taste aversion is also seen in the inbred variants, in both males and females. In other experiments, we asked whether HDID mice would ingest sufficient doses of ethanol to lead to a conditioned taste aversion upon retest. Different manipulations were used to elevate consumption of ethanol on initial exposure. Access to increased ethanol concentrations, to multiple tubes of ethanol, and fluid restriction to increase thirst motivation all enhanced initial drinking of ethanol. Each condition led to reduced intake the next day, consistent with a mild conditioned taste aversion. These experiments support the conclusion that one reason contributing to the willingness of HDID mice to drink to the point of intoxication is a genetic insensitivity to the aversive effects of ethanol.

Alcohol use disorders (AUDs) are prevalent, and are characterized by binge-like drinking, defined by patterns of focused drinking where dosages ingested in 2–4 ​h reach intoxicating blood alcohol levels (BALs). Current medications are few and compliance with the relatively rare prescribed usage is low. Hence, novel and more effective medications are needed. We developed a mouse model of genetic risk for binge drinking (HDID: High Drinking in the Dark mice) by selectively breeding for high BALs after binge drinking. A transcriptional analysis of HDID brain tissue with RNA-Seq implicated neuroinflammatory mechanisms, and, more specifically extracellular matrix genes, including those encoding matrix metalloproteinases (MMPs). Prior experiments from other groups have shown that the tetracycline derivatives doxycycline, minocycline, and tigecycline, reduce binge drinking in inbred C57BL/6J mice. We tested these three compounds in female and male HDID mice and found that all three reduced DID and BAL. They had drug-specific effects on intake of water or saccharin in the DID assay. Thus, our results show that the effectiveness of synthetic tetracycline derivatives as potential therapeutic agents for AUDs is not limited to the single C57BL/6J genotype previously targeted, but extends to a mouse model of a population at high risk for AUDs., Highlights • Doxycycline, minocycline, and tigecycline reduce binge alcohol drinking in high risk mice. • Female and male mice are responsive. • These data show that synthetic tetracycline derivatives are potential therapeutic agents for alcohol use.

Despite acceptance that risk for alcohol-use disorder (AUD) has a large genetic component, the identification of genes underlying various components of risk for AUD has been hampered in humans, in part by the heterogeneity of expression of the phenotype. One aspect of AUD is physical dependence. Alcohol withdrawal is a serious consequence of alcohol dependence with multiple symptoms, many of which are seen in multiple species, and can be experienced over a wide-ranging time course. In the present three studies, we developed a battery of withdrawal tests in mice, examining behavioral symptoms from multiple domains that could be measured over time. To permit eventual use of the battery in different strains of mice, we used male and female mice of a genetically heterogeneous stock developed from intercrossing eight inbred strains. Withdrawal symptoms were assessed using commonly used tests after administration of ethanol in vapor for 72 continuous hours. We found significant effects of ethanol withdrawal versus air-breathing controls on nearly all symptoms, spanning 4 days following ethanol vapor inhalation. Withdrawal produced hypothermia, greater neurohyperexcitability (seizures and tremor), anxiety-like behaviors using an apparatus (such as reduced transitions between light and dark compartments), anhedonia (reduced sucrose preference), Straub tail, backward walking, and reductions in activity; however, there were no changes in thermal pain sensitivity, hyper-reactivity to handling, or anxiety-like emergence behaviors in other apparatus. Using these data, we constructed a refined battery of withdrawal tests. Individual differences in severity of withdrawal among different tests were weakly correlated at best. This battery should be useful for identifying genetic influences on particular withdrawal behaviors, which should reflect the influences of different constellations of genes.

Background There is a serious public health need for better understanding of alcohol use disorder disease mechanisms and for improved treatments. At this writing, only three drugs are approved by the Food and Drug Administration as medications to treat alcohol use disorders – disulfiram, naltrexone, and acamprosate. Binge drinking is a form of abusive alcohol drinking defined by the NIAAA as a drinking to blood alcohol levels (BALs) > 0.08% during a period of approximately 2 h. To model genetic risk for binge-like drinking, we have used selective breeding to create a unique animal model, High Drinking in the Dark (HDID) mice. Behavioral characterization of HDID mice has revealed that HDID mice exhibit behavioral impairment after drinking, withdrawal after a single binge-drinking session, and escalate their intake in response to induction of successive cycles of dependence. Notably, HDID mice do not exhibit altered tastant preference or alcohol clearance rates. We therefore asked whether drugs of known clinical relevance could modulate binge-like ethanol drinking in HDID mice, reasoning that this characterization of HDID responses should inform future use of this genetic animal model for screening and development of novel potential therapeutics. Methods We tested the efficacy of acamprosate and naltrexone to reduce binge-like drinking in HDID mice. Additionally, we tested the GABA B receptor agonist, baclofen, based on recent pre-clinical and clinical studies demonstrating that it reduces alcohol drinking. We elected not to include disulfiram due to its more limited clinical usage. Mice were tested after acute doses of drugs in the limited-access Drinking in the Dark (DID) paradigm. Results HDID mice were sensitive to the effects of acamprosate and baclofen, but not naltrexone. Both drugs reduced binge-like drinking. However, naltrexone failed to reduce drinking in HDID mice. Thus, HDID mice may represent a useful model for screening novel compounds.

The broad-spectrum herbicide glufosinate ammonium is a structural analogue of glutamate and acts in plants by inhibition of glutamine synthetase leading to a complete breakdown of ammonia metabolism. Owing to the structural analogy of glufosinate ammonium to glutamate, its effect on various glutamate-utilizing systems needed to be investigated in mammals. Although in laboratory animals glufosinate ammonium causes an inhibition of glutamine synthetase activity in different tissues, this inhibition led to slight increases of glutamate and ammonia levels at high sublethal and lethal doses only. After oral administration for 28 days, glufosinate ammonium had no effect on glutathione and carbohydrate metabolism and no effect on biosynthesis of non-essential amino acids in rats and dogs. Glufosinate ammonium does not interfere with various neurotransmitter receptors in vitro and does not influence the catecholamine neurotransmitter tissue concentrations after iv application. The results of these studies show that—in contrast to the plant metabolism—in mammals the inhibition of glutamine synthetase activity in various tissues does not lead to a breakdown of ammonia metabolism. The mammalian metabolism obviously compensates for this inhibition of glutamine synthetase activity by various other metabolic pathways. It is concluded that under the conditions of recommended use of glufosinate ammonium as an active ingredient in herbicides, a detrimental effect on the health of both users and consumers is extremely unlikely.

This paper reviews the results of toxicity studies conducted in laboratory animals to evaluate the safety of the herbicide trifluralin (TFL). The data show that TFL is slightly toxic following single oral exposure. Testing for embryotoxicity in rats and rabbits indicated no teratogenic potential, and many different mutagenicity tests showed that TFL was non-genotoxic. Subchronic and chronic toxicity testing in rats, mice and dogs indicated that TFL was haematotoxic (anaemia and methaemoglobinaemia), particularly in the dog, and slightly hepatotoxic. No-observed-effect levels of 4.8 and 41 mg/kg body weight/day, respectively, were determined in dogs and rats exposed chronically to TFL. Oncogenicity studies in rats and mice revealed no carcinogenic potential. Since the data for TFL indicated no mutagenic or other special toxicological risks, it is suggested that a safety factor of 100 could be used for the determination of the acceptable daily intake of TFL, which would be 0.05 mg/kg body weight/day.

Traditional cultivar Grüner Veltliner is the most appreciated vine in Austrian viticulture. Due to organic growing the demand for mildew resistance within the same wine profile has increased. Cross breeding can provide such new genotypes which combine traits from different sources by parenthood. Linkage of traits with chromosomes or markers allows to predict some aspects of the phenotype. Equipped with chromosomal assisted selection the development of new varieties could be much easier and faster. On the base of two segregating populations derived from crosses of Grüner Veltliner with Malverina and Seyval blanc we could define correlation of chromosomes with some traits. Mainly ampelographic descriptors and resistance against mildew could be aligned. As a quality parameter of the wine Rotundone analyses were performed and could be attributed to chromosome 5 and 9. Selection supported by the composition of the parental chromosomes enables breeding with some arguments of design. The limits for free choice were the availability of sufficient different genotypes with a broad spectrum of chromosomal combinations. Recently released descendent cultivar Donauveltliner was selected due to the high rate of Traminer alleles.

The insecticide endosulfan was evaluated for chronic toxicity and carcinogenicity in long-term feeding studies in both Sprague-Dawley rats and NMRI mice. Dietary concentrations of the test substance were administered to rats at 0, 3, 7.5, 15 and 75 ppm and to mice at 0, 2, 6 and 18 ppm for 24 months each. In the rat study, only the treatment with the highest dose caused a significant reduction of body weight gains of the males and females at 75 ppm. The increased incidence of enlarged kidneys seen at autopsy at 75 ppm in females, and the slightly increased incidence of progressive glomerulonephrosis and slightly increased incidence of renal aneurysms seen histopathologically in the 75 ppm males, make the kidney the target organ in rats. On the basis of these findings a dietary concentration of 15 ppm is considered to be the no-observed-effect level (NOEL) in rats, equivalent to a daily test substance intake of 0.6 mg/kg body weight in males and 0.7 mg/kg body weight in females. In the mouse study, the treatment with 18 ppm caused a significant increase of mortality in the females and a slight (in the first third of the study, significant) reduction of body weight gain in males. Since there were no other substance-related findings, the dietary concentration of 6 ppm is considered to be the NOEL in mice, equivalent to a daily test substance intake of 0.84 mg/kg body weight in males and 0.97 mg/kg body weight in females. An evaluation of all relevant tumour data gained in both studies revealed no differences between control and treated groups. It was concluded, therefore, that endosulfan has no carcinogenic potential.

After immunization of six BALB/c mice with saxitoxin (STX) coupled to keyhole limpet hemocyanin only one mouse developed serum antibodies specific to STX. By hybridizing the splenocytes of this mouse with X63‐Ag8.653 myeloma cells one hybridoma line secreting antibodies to STX was produced. The antibody was designated 5C2 and proved to be IgM. In an indirect enzyme immunoassay using STX coupled to bovine serum albumin as the immobilized phase, the monoclonal antibody reacted with free STX in a concentration range of 4 to 10 μg per ml.

The quality of vacuum sintered material strongly depends on the gas atmosphere during the various sintering steps. This gas atmosphere depends on the furnace outgassing, possibly on added protective or reactive gases, and on outgassing of the load. With a computer-controlled quadrupole mass spectrometer the gas composition in a vacuum furnace was determined quantitatively. The gas sampling position was inside the furnace to determine the gas composition nearest to the sintering material. In several runs, the empty furnace, the degassing of samples under vacuum conditions, and the reaction of samples upon different added gases was monitored. The mechanical and physical properties of the sintered material were investigated to see the influence of the different gas compositions of the quality. It will be shown that, monitoring of the sintering furnace atmosphere with a mass spectrometer gives a good opportunity to optimize the temperature vs time profile of the sintering process and to precisely control the product quality.

A monoclonal antibody to the trichothecene mycotoxin diacetoxyscirpenol (DAS) was produced by a hybridoma, designated 2E5. It secreted antibody of the IgGl subclass and had a detection limit for DAS of 16 ng/ml with a direct enzyme immunoassay on a double antibody solid phase. The relative cross-reactivities with 3α-acetyl-DAS, diacetylverrucarol, neosolaniol, T-2 tetraol tetraacetate, fusarenon X, T-2 toxin, and HT-2 were 2224·5, 53·7, 13·9, 9·2, 6·4, 1·7, 0·6, and 0·35%, respectively.

A monoclonal antibody to chloramphenicol (CAP) was produced. After immunization of BALB/c mice with CAP base coupled to human serum albumin and incubation of the stimulated splenocytes in vitro in the presence of antigen for three days, these splenocytes were hybridized with X63‐Ag8·653 myeloma cells. The antibody, designated 6A10, proved to be IgG2b, and it had a detection limit for CAP of 10 ng/ml (0·5 ng/assay) in the direct enzyme immunoassay using horseradish peroxidase‐labelled CAP. The cross‐reactivities with CAP base, p‐nitrobenzyl alcohol, and p‐nitrophenol were 5·0, 0·94, and 0·007%, respectively. No cross‐reactivities were observed with penicillin, tetracycline and thiamphenicol, respectively.

Polyclonal and monoclonal antibodies against fusarenon‐X were prepared by using a fusarenon‐X oxime derivative coupled to human serum albumin as the antigen for the immunization of rabbits and BALB/c mice, respectively. The specificity and sensitivity of these antibodies were tested by using fusarenon‐X oxime coupled to horseradish peroxidase as an enzyme‐linked toxin in a competitive assay with a double antibody solid phase. The relative cross‐reactivities of the polyclonal antiserum with T‐2 toxin, diacetoxyscirpenol, fusarenon‐X and neosolaniol were 3.67, 2.75, 1.0 and 0.58, respectively. The monoclonal antibody, however, showed considerable cross‐reactivity only with neosolaniol (0.28). The detection limit for fusarenon‐X was 150 pg/ml (5 pg per assay) and 300 pg/ml (10 pg per assay), respectively, using the polyclonal and monoclonal antibodies.

Thirteen monoclonal antibodies reactive with HT-2 were prepared by using a HT-2 hemisuccinate coupled to human serum albumin as antigen for the immunization of BALB/c mice. In a competitive enzyme immunoassay on a double antibody solid phase using HT-2 hemisuccinate coupled to horseradish peroxidase as enzyme linked toxin all antibodies reacted much better with T-2 toxin and acetyl T-2 than with HT-2. Eleven antibodies showed almost the same sensitivity and specificity, and one of these, designated 3E2, is extensively described. Its cross-reactivities with HT-2, T-2 toxin, acetyl T-2, iso T-2, T-2 tetraol tetraacetate and T-2 triol were 1·0, 140·2, 161·2, 0·32, 0·14 and 0·016, respectively. Two other antibodies, designated 2A4 and 2A5, behaved quite differently. The cross-reactivities of antibody 2A4 with these toxins were: 1·0, 113·9, 374·4, 1·35, 0·34 and 0·023, respectively; for antibody 2A5 they were 1·0, 46·1, 155·4, 8·31, 0·9 and 0·08, respectively. All antibodies proved to be IgGl. By using the antibody 3E2 a highly sensitive and very specific enzymc immunoassay for the detection of T-2 toxin was developed. The detection limit for T-2 toxin was 5 pg/ml (0·25 pg/assay).

Two murine monoclonal antibodies to the macrocyclic trichothecene roridin A are described. Screening for antibody production was performed on absorbed anti-mouse immunoglobulin serum as double-antibody solid phase, and further characterization was done on affinity-purified anti-mouse IgG serum. The antibodies, designated 5G11 and 4H10, had affinity constants for roridin A of 9.25 X 10(7) and 1.7 X 10(7) liters/mol, respectively. In monoclonal antibody-based direct enzyme immunoassays, these IgG1 antibodies had detection limits for roridin A of 0.4 ng/ml (0.02 ng per assay) and 1.8 ng/ml (0.09 ng per assay), respectively. Both antibodies were most specific for the tested macrocyclic trichothecenes. The relative cross-reactivities of antibody 5G11 with roridin A, roridin J, verrucarin A, satratoxin G, and satratoxin H were 100.0, 43.8, 16.7, 3.7, and 18.9%, respectively; for antibody 4H10 they were 100.0, 6.3, 64.0, 4.4, and 4.9%, respectively.

Summary A new method for the screening of monoclonal antibodies to mycotoxins was developed using a double antibody solid phase in a direct enzyme immunoassay. Wells of microtitre plates were coated with affinity-purified anti-mouse IgG antiserum. The monoclonal antibody against the trichothecene T-2 toxin bound to this solid phase was detected by reaction with an HT-2 toxin-peroxidase conjugate. The monoclonal antibody belongs to the IgG 1 subclass and has a detection limit for T-2 toxin of 50ng/ml in a competitive direct enzyme immunoassay. The relative cross-reactivity with acetyl T-2, HT-2, iso T-2, T-2 triol and T-2 tetraol-tetraacetate was 0.75, 0.35, 0.35, 0.22 and 0.01, respectively. No cross-reactions with other trichothecenes could be found. Zusammenfassung Ein monoklonaler Antikorper gegen das Trichothecen T-2 Toxin: Screening des Antikorpers mit einem direkten Enzymimmunoassay Fur das Screening von monoklonalen Antikorpern gegen Mykotoxine wurde eine neue Methode entwickelt. Es wird ein direkter Enzymimmunoassay mit einer “Double antibody solid phase” verwendet, bei dem die Kavitaten der Mikrotiterplatte mit affinitatschromatographisch gereinigtem Anti-Maus IgG-Antiserum beschichtet werden. Der gebundene monoklonale Antikorper gegen T-2 Toxin wurde durch die Reaktion mit einem HT-2 Toxin-Peroxidase-Konjugat nachgewiesen. Der monoklonale Antikorper gehorte zur IgG 1-Subklasse und hatte im direkten kompetitiven Enzymimmunoassay eine Nachweisgrenze von 50 ng/ml fur T-2 Toxin. Die relative Kreuzreaktivitat mit Acetyl T-2, HT-2, Iso T-2, T-2 Triol und T-2 Tetraoltetraacetat betrug 0,75, 0,35, 0,35, 0,22 und 0,01. Mit anderen Trichothecenen wurden keine Kreuzreaktionen gefunden.