1,720,960 research outputs found
Ethanol induces conditioned place preference in genetically selected alcohol-preferring rats
No full textThe study of the biological mechanisms of ethanol reward has greatly suffered from problems to obtain ethanol-induced conditioned place preference (CPP) in rats. In the present study, CPP was obtained in genetically selected Marchigian Sardinian alcohol-preferring (msP) rats, derived from Sardinian alcohol-preferring rats, following intragastric (IG) ethanol administration by means of a permanent IG catheter, but not after intraperitoneal (IP) injection or IG gavage. Rats with permanent IG catheter; received IG administration of 0.35, 0.7, 1.5 or 2.8 g/kg ethanol, as a 10% v/v solution. In ethanol-experienced rats 0.7 or 1.5, but not 0.35 or 2.8 g/kg ethanol significantly increased in comparison to controls the time spent in the ethanol-associated previously non-preferred compartment, which became preferred in the postconditioning test. In ethanol-naive rats, only 0.7 g/kg ethanol significantly increased the time spent in the ethanol-associated compartment. On the other hand, no effect was observed in alcohol-experienced rats following IG gavage, or IP injection of 0.35, 0.7 or 1.5 g/kg ethanol. The present results provide evidence that ethanol possesses post-ingestive rewarding properties in msP rats, and that it can reliably induce CPP in them, provided that an appropriate method of administration is adopted
Antidepressant-like effect of ethanol revealed in the forced swimming test in Sardinian alcohol-preferring rats
No full textRationale: A large body of evidence indicates high comorbidity between depression and alcohol abuse. The self-medication hypothesis proposes that depressed subjects may abuse ethanol because it reduces the symptoms of depression. The present study evaluated whether ethanol may exert an antidepressant-like action in genetically selected alcohol-preferring rats, either Sardinian alcohol-preferring (sP)or Marchigian Sardinian alcohol- preferring (msP) rats, and for comparison in Sardinian alcohol-non-preferring (sNP) rats. Methods: The forced swimming test (FST) was used to evaluate the antidepressant-like action of ethanol; in this test the effect of ethanol ingestion on the immobility time was determined. Results: Ethanol-naive sP rats exhibited a longer period of immobility in comparison to sNP rats. Both in ethanol-naive sP and msP rats, voluntary ethanol drinking reduced the immobility time. A similar effect was obtained when repeated (five or nine) intragastric administrations of 0.7 g/kg ethanol were given during the 24 h prior to the test in msP and in sP, but not in sNP rats. Desipramine, like ethanol, sharply reduced immobility at doses of 5 or 20 mg/kg, given 3 times in the 24 h before the test in msP rats. The reduced immobility induced by ethanol in msP rats was apparently not the consequence of a general motor activation, because 9 IG administrations of ethanol, 0.7 g/kg, failed to alter locomotor activity in the open field test. Moreover, blood alcohol levels and rectal temperature of msP, sP and sNP after IG ethanol administration were not statistically different. Conclusions: The present results provide evidence for an antidepressant-like action of ethanol in sP and msP rats and suggest that this action may contribute to sustain their high ethanol drinking
Mechanism of action for reduction of ethanol intake in rats by the tachykinin NK-3 receptor agonist aminosenktide
No full textIntracerebroventricular (ICV) injection of tachykinin (TK) NK-3 receptor agonists inhibits alcohol intake in genetically selected alcohol-preferring rats. The present study investigated the mechanism of action by which the selective TK NK-3 receptor agonist aminosenktide (NH2-SENK) attenuates ethanol intake in Marchigian Sardinian alcohol-preferring (msP) rats. The effect of NH2-SENK was studied by ICV injection in the conditioned taste aversion (CTA) and in the conditioned place preference (CPP) paradigms; moreover, the effect of NH2-SENK on blood alcohol levels (BAL) following intragastric ethanol administration was investigated. The ICV dose of 125 ng/rat of NH2-SENK, that markedly reduces ethanol intake, did not modify BAL, nor did it increase the CTA induced by intraperitoneal injection of ethanol, 1 g/kg body weight. These findings suggest that the effect of NH2-SENK on alcohol consumption is not related to modification of the pharmacokinetics of ethanol, nor to increase of the aversive properties of ethanol. On the other hand, the same ICV dose of NH2-SENK evoked a pronounced and statistically significant CPP. This finding indicates that the TK NK-3 receptor agonist NH2-SENK possesses rewarding properties in msP rats and suggests that its inhibitory effect on ethanol consumption may be due to substitution of the rewarding properties of ethanol, thus making its consumption redundant. Copyright (C) 1998 Elsevier Science Inc
Effect of the thyreotropin releasing hormone analogue posatirelin (RGH 2202) on microanatomical changes induced by lesions of the nucleus basalis magnocellularis in the rat
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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