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Cardoso Cruz, F.

Publications and source records attributed to Cardoso Cruz, F..

2 recordsLinked to original sources

Pursuing reconsolidation in ethanol-CPP: memory reactivation in different conditions did not trigger destabilization

Consolidated memories can return to a labile state during retrieval, through destabilization, and must be reconsolidated to persist. Associative memories of contextual cues paired with hedonic effects of drugs of abuse exert a pivotal role in maintaining maladaptive behaviors in addiction. Thus, impairment of reconsolidation of drug-associated memories may provide a potential strategy to reduce drug-seeking and relapse in addiction. It is critical to understand the conditions under which a consolidated memory becomes labile and may undergo reconsolidation. After inducing ethanol Conditioned Place Preference (CPP; 2 g/kg ethanol, i.p.) in male mice, we examined different parameters during the reactivation session that could turn memory susceptible to disruption by systemic injection of the protein synthesis inhibitor cycloheximide (CHX, 100 mg/kg, i.p.). Reactivation with free access to the apparatus (similarly to a Test session, for 10, 5, or 3 min) or Reactivation sessions restricted to ethanol-paired compartment with no ethanol (for 10 or 5 min), or with the administration of a low dose of ethanol (5 min session), failed to reduced ethanol-preference after CHX administration. These findings suggest that boundary conditions constraint memory in ethanol-CPP to undergo reconsolidation.

neuroscience↗

Effect Of Ayahuasca on Experimental Models of Ethanol Addiction and Immunohistochemistry Analysis in Rodents

BackgroundAyahuasca, a psychoactive Amazonian preparation, is increasingly studied for substance-use disorders. ObjectivesInvestigate whether oral lyophilised-ayahuasca attenuates ethanol-induced conditioned place preference (CPP) in mice and alters {Delta}FosB expression in nucleus accumbens (NAc). MethodsMale Swiss mice received water or ayahuasca (130-1950 mg/kg, p.o.) 30 min before each of eight ethanol pairings (2g/kg i.p.) in a CPP paradigm. A separate cohort underwent acute toxicology (650-5000mg/kg) with behavioural-observation and rotarod. Alkaloids were quantified by LC-MS/MS. {Delta}FosB-immunoreactive nuclei were counted in NAc 24h after the CPP post-test. ResultsAlkaloids levels were within traditional ranges. High-dose ayahuasca(5000 mg/kg) produced transient-serotonergic-syndrome-like signs and rotarod locomotor-deficit; lower doses did not express toxicity. Ethanol produced a moderate-CPP in controls({Delta}Time{approx}+60s), whereas ayahuasca-pretreatment abolished preference at all doses({Delta}Time within{+/-}7s). One-way ANOVA on {Delta}Time showed a robust-Treatment effect(F(3,36)=8.83, p=0.00016); Tukey tests: control differed from each ayahuasca group (all p<0.05), with no differences among ayahuasca doses. {Delta}FosB density did not differ among groups(p>0.05). ConclusionsAyahuasca was well tolerated at ceremonies-equivalent doses and blocked ethanol-induced-CPP across all doses, while {Delta}FosB levels in NAc were unchanged at 24h. Limitations on the CPP baseline and {Delta}FosB results may limit sensitivity, generalisability and interpretation. Findings provide preliminary evidence that ayahuasca-pretreatment may blunt ethanol-context preference, reinforcing the need of replication with stronger reward baselines, naive controls and complementary molecular markers.

pharmacology and toxicology↗