Navegando por Palavras-chave "behavioural sensitization"
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- ItemSomente MetadadadosChronic amphetamine transforms the emotional significance of a novel but not a familiar environment: implications for addiction(Cambridge Univ Press, 2011-08-01) Fukushiro, Daniela Fukue [UNIFESP]; Frussa Filho, Roberto [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Both drug-induced locomotor sensitization and reactivity to novelty in rodents have been related to drug-craving mechanisms in humans. We investigated whether the exposure to a completely novel environment would modulate the expression of locomotor sensitization induced by repeated administration of amphetamine (Amp) in mice. in addition to locomotion, different open-field behavioural parameters were used to evaluate the possible involvement of anxiogenic-like effects induced by Amp, novelty or a combination of the two. in order to avoid misinterpretations due to different locomotor baseline conditions, we used an open-field illumination condition in which previous exposure to the apparatus did not modify locomotion (although it reliably increased grooming behaviour). Acute Amp administration increased locomotion in mice previously habituated to the open field (Hab) but not in mice exposed to the apparatus for the first time (Nov). This absence of Amp-induced locomotor activation in Nov mice may be related to higher anxiety-like levels, because these animals displayed longer freezing duration. However, only Nov mice developed locomotor sensitization. Because Amp challenge in Amp pre-treated Nov mice did not induce an increase in freezing behaviour, the locomotor sensitization in Nov mice might be related to the tolerance of Amp-induced anxiogenic-like behaviour in novel environments. Repeated Amp administration increased motivation to explore the environment in Nov mice in that these animals presented a within-session locomotion-habituation deficit. Our data suggest that a complex and plastic interaction between the anxiogenic and motivational properties of both novelty and Amp can critically modify the behavioural expression of craving-related mechanisms.
- ItemSomente MetadadadosLong maternal separation accelerates behavioural sensitization to ethanol in female, but not in male mice(Elsevier B.V., 2007-12-03) Kawakami, Suzi Emiko; Quadros, Isabel Marian Hartmann; Takahashi, Shirley; Suchecki, Deborah; Universidade Federal de São Paulo (UNIFESP); Tufts UnivEarly life stress is associated with dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis, and with aspects involved in drug abuse. in this study, we investigated the effects of brief (BMS) and long maternal separation (LMS) on the HPA axis response and behavioural sensitization to ethanol (EtOH) in male and female mice. From PND 2 to 14, pups were subjected to daily maternal separation for 15 min (BMS) or 180 min (LMS) or no separated, only handled during cage cleaning (animal facility rearing-AFR). As adults, animals were treated every other day with saline (SAL) or EtOH (2.2 g/kg), i.p., for 10 days, and immediately after each administration, their locomotor response was evaluated for 15 min. Forty-eight hours after the 5th administration, all animals were challenged with saline, followed 48 h later, by an EtOH challenge. Corticosterone (CORT) plasma levels were determined 3 times: basal, after the 1st administration and after the EtOH challenge. LMS females showed higher CORT levels than BMS females at basal, but not in response to acute or chronic EtOH administration. the CORT response to EtOH was more robust in LMS and BMS male than AFR male mice. Repeated EtOH treatment induced behavioural sensitization in all groups of male mice. in females, LMS induced a faster sensitization, although BMS females also exhibited behavioural sensitization (4th day and 5th day of treatment, respectively). in conclusion, LMS and BMS produced gender-dependent effects. in females, LMS and BMS facilitated the development of behavioural sensitization, but in the LMS group this effect occurred faster, which may represent increased vulnerability to drug abuse. Moreover, LMS females showed higher basal CORT levels compared to BMS. in males, LMS and BMS increased the CORT response to EtOH but did not modify behavioural sensitization. Therefore, we postulate that LMS female mice exhibited a faster development of behavioural sensitization, but CORT levels were not involved with this effect. (c) 2007 Elsevier B.V. All rights reserved.
- ItemSomente MetadadadosSelective action of an atypical neuroleptic on the mechanisms related to the development of cocaine addiction: a pre-clinical behavioural study(Cambridge Univ Press, 2014-04-01) Marinho, Eduardo Ary Villela; Oliveira-Lima, Alexandre Justo de [UNIFESP]; Wuo-Silva, Raphael [UNIFESP]; Santos, Renan [UNIFESP]; Baldaia, Marilia Araujo [UNIFESP]; Hollais, André Willian [UNIFESP]; Longo, Beatriz Monteiro [UNIFESP]; Berro, Laís Fernanda [UNIFESP]; Frussa-Filho, Roberto [UNIFESP]; Univ Estadual Santa Cruz; Universidade Federal de São Paulo (UNIFESP)An increased function in the mesolimbic dopaminergic system has been extensively associated with the rewarding effects of both natural stimuli and drugs of abuse. Thus, dopamine receptor blockers, such as neuroleptic drugs, can be proposed as candidates for potential therapeutic approaches to treat drug dependence. Notwithstanding, this therapeutic potential of neuroleptics critically depends on a selective action on the specific mechanisms related to the development of addiction. We compared the effects of different doses of haloperidol, ziprasidone and aripiprazole (first-, second- and third-generation neuroleptics, respectively) on spontaneous locomotor activity of mice in a novel environment, hyperlocomotion induced by acute cocaine administration and cocaine-induced locomotor sensitization by a two-injection protocol. Whereas high doses of haloperidol abolished the three behavioural paradigms without selectivity, low doses of ziprasidone selectively abolished the development of the behavioural sensitization phenomenon. Finally, low doses of aripiprazole inhibited acute cocaine-induced hyperlocomotion and behavioural sensitization without modifying spontaneous locomotor activity. Thus, aripiprazole at lower doses was the most selective antipsychotic drug concerning the inhibition of the development of behavioural sensitization to cocaine. Because locomotor sensitization in rodents has been proposed to share plastic mechanisms with drug addiction in humans, our data provide relevant suggestions to the clinical practice.