1,720,990 research outputs found
Differential diurnal variations of anandamide and 2-arachidonoyl-glycerol levels in rat brain
No full textThe 1,2,3-triazole ring as a peptido- and olefinomimetic element: discovery of click vanilloids and cannabinoids
No full textThe NOP receptor involvement in both withdrawal- and CCk-8-induced contracture responses of guinea pig isolated ileum after acute activation of κ-opioid receptor
No full textIn isolated guinea-pig ileum (GPI), the κ-opioid acute withdrawal response is
under the control of several neuronal signaling systems, including the μ-opioid,
the A(1)-adenosine and the CB(1) receptors, which are involved in the inhibitory
control of the κ-withdrawal response. After κ-opioid system stimulation, indirect
activation of μ-opioid, A(1)-adenosine and CB(1) systems is prevented by the
peptide cholecystokinin-8 (CCk-8). In the present study, we have investigated
whether the NOP system is also involved in the regulation of the acute
κ-withdrawal response. Interestingly, we found that in GPI preparation, the NOP
system is not indirectly activated by the κ-opioid receptor stimulation, but
instead this system is able by itself to directly regulate the acute κ-withdrawal
response. Specifically, our results clearly highlight first the existence of an
endogenous tone of the NOP system in GPI, and second that it behaves as a
functional anti-opioid system. We also found that, the NOP receptor system is
involved in the regulation of the CCk-8-induced contracture intensity, only when
in the presence of the κ-opioid receptor stimulation. This effect seems to be
regulated by an activation threshold mechanism. In conclusion, the NOP system
could act as neuromodulatory system, whose action is strictly related to the
modulation of both excitatory and inhibitory neurotransmitters released in GPI
enteric nervous system
Inhibition of colon carcinogenesis by a standardized Cannabis sativa extract with high content of cannabidiol.
No full textChronic morphine modulates the contents of the endocannabinoid, 2-arachidonoyl glycerol, in rat brain
No full textChanges in endocannabinoid levels in a rat model of behavioural sensitization to morphine
No full textThe opioid and cannabinoid systems co-operate to regulate physiological processes such as nociception and reward. The endocannabinoid system may be a component of the brain reward circuitry and thus play a role not only in cannabinoid tolerance/dependence, but also in dependence/withdrawal for other misused drugs. We provide evidence of a cannabinoid mechanism in an animal model of morphine drug-seeking behaviour, referred to as behavioural sensitization. The present study was designed to test the effects of the CB1 cannabinoid receptor antagonist SR141716A in two different phases of morphine sensitization (induction and expression) and to measure the brain contents of arachidonoylethanolamide (anandamide, AEA) and 2-arachidonoylglycerol (2-AG), the two main endogenous ligands for cannabinoid receptors in the different phases of morphine sensitization. The cannabinoid antagonist modified the signs of morphine sensitization when administered in the expression phase, whereas co-administration of SR141716A and morphine in the induction phase only slightly affected the behavioural responses, suggesting that CB1 receptor blockade attenuates the behavioural manifestations of morphine sensitization but not its development. AEA and 2-AG were affected differently by morphine during the two phases of behavioural sensitization. The alterations were in opposite directions and specific for the cerebral area analysed (caudate putamen, nucleus accumbens, hippocampus and prefrontal cortex). The results suggest that the endocannabinoid system undergoes profound changes during the different phases of sensitization to morphine in rats, providing a possible neurochemical basis for the previously observed cross-sensitization between opiates and cannabinoids
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
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