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Alcohol interferes with foetal development and prenatal alcohol exposure can lead to adverse effects known as foetal alcohol spectrum disorders. We aimed to assess the underlying neurobiological mechanisms involved in alcohol intake and withdrawal in adolescent mice exposed to alcohol during early life stages, in discrete brain areas. Pregnant C57BL/6 female mice were exposed to binge alcohol drinking from gestation to weaning. Subsequently, alcohol seeking and taking behaviour were evaluated in male adolescent offspring, as assessed in the two-bottle choice and oral self-administration paradigms. Brain area samples were analysed to quantify AMPAR subunits GluR1/2 and pCREB/CREB expression following alcohol self-administration. We measured the expression of mu and kappa opioid receptors both during acute alcohol withdrawal (assessing anxiety alterations by the EPM test) and following reinstatement in the two-bottle choice paradigm. In addition, alcohol metabolism was analysed by measuring blood alcohol concentrations under an acute dose of 3 g/kg alcohol. Our findings demonstrate that developmental alcohol exposure enhances alcohol intake during adolescence, which is associated with a decrease in the pCREB/CREB ratio in the hippocampus, prefrontal cortex and striatum, while the GluR1/GluR2 ratio showed a decrease in the hippocampus. Moreover, PLAE mice showed behavioural alterations, such as increased anxiety-like responses during acute alcohol withdrawal, and higher BAC levels. No significant changes were identified for mu and kappa opioid receptors mRNA expression. The current study highlights that early alcohol exposed mice increased alcohol consumption during late adolescence. Furthermore, a diminished CREB signalling and glutamatergic neuroplasticity are proposed as underpinning neurobiological mechanisms involved in the sensitivity to alcohol reinforcing properties. This work was supported by the Ministerio de Economía y Competitividad (SAF2016-75966-R-FEDER and SAF-2017-85679-R-FEDER), and the Ministerio de Sanidad, Consumo y Bienestar Social (Plan Nacional sobre Drogas 2018/007, Retic-ISCIII-RD16/0017/0010 and Retic-ISCIII-RD16/0017/0007). SM-R received a postdoctoral fellowship from the Conselleria d'Educació, Investigació, Cultura i Esport (APOSTD/2017/102), Generalitat Valenciana, Spain. LC received an FPI grant (BES-2014-070657) from the Ministerio de Economía y Competitividad, Spain. The Department of Experimental and Health Sciences (UPF) is a “Unidad de Excelencia María de Maeztu” funded by the AEI (CEX2018-000792-M). The authors thank Gerald-Patrick Fannon for his English proofreading and editing of the manuscript. The authors declare no conflicts of interest.

The single-dose disposition kinetics of cefonicid were determined in clinically normal lactating goats (n=6) after intravenous (IV), intramuscular (IM) and subcutaneous (SC) administration of a conventional formulation, and after subcutaneous administration of a long-acting formulation (SC-LA). Cefonicid concentrations were determined by high performance liquid chromatography with ultraviolet detection. The concentration-time data were analyzed by non-compartmental pharmacokinetic methods. Steady-state volume of distribution (Vss) and clearance (Cl) of cefonicid after IV administration were 0.14  0.03 L/kg and 0.51  0.07 L/h·kg, respectively. Following IM, SC and SC-LA administration, cefonicid achieved maximum plasma concentrations of 14.46  0.82, 11.98  1.92 and 17.17  2.45 mg/L at 0.26  0.13, 0.42  0.13 and 0.83  0.20 hours, respectively. The absolute bioavailabilities after IM, SC and SC-LA routes were 75.34  11.28 %, 71.03  19.14 % and 102.84  15.155 %, respectively. After cefonicid analysis from milk samples, no concentrations were found above LOQ at any sampling time. From these data, cefonicid administered at 20 mg/kg each 12 hours after SC-LA could be effective to treat bacterial infections in lactating animals not affected by mastitis problems.

Relapse in the seeking and intake of cocaine is one of the main challenges when treating its addiction. Among the triggering factors for the recurrence of cocaine use are the re-exposure to the drug and stressful events. Cocaine relapse engages the activity of memory-related nuclei, such as the basolateral amygdala (BLA) and the hippocampal dentate gyrus (DG), which are responsible for emotional and episodic memories. Moreover, D3 receptor (D3R) antagonists have recently arisen as a potential treatment for preventing drug relapse. Thus, we have assessed the impact of D3R blockade in the expression of some dopaminergic markers and the activity of the mTOR pathway, which is modulated by D3R, in the BLA and DG during the reinstatement of cocaine-induced conditioned place preference (CPP) evoked by drug priming and social stress. Reinstatement of cocaine CPP paralleled an increasing trend in D3R and dopamine transporter (DAT) levels in the BLA. Social stress, but not drug-induced reactivation of cocaine memories, was prevented by systemic administration of SB-277011-A (a selective D3R antagonist), which was able, however, to impede D3R and DAT up-regulation in the BLA during CPP reinstatement evoked by both stress and cocaine. Concomitant with cocaine CPP reactivation, a diminution in mTOR phosphorylation (activation) in the BLA and DG occurred, which was inhibited by D3R blockade in both nuclei before the social stress episode and only in the BLA when CPP reinstatement was provoked by a cocaine prime. Our data, while supporting a main role for D3R signalling in the BLA in the reactivation of cocaine memories evoked by social stress, indicate that different neural circuits and signalling mechanisms might mediate in the reinstatement of cocaine-seeking behaviours depending upon the triggering stimuli.

Aims: Oxidative stress caused by exposure to drugs of abuse such as ethanol or 3, 4 methylenedioxymethamphetamine (MDMA) may derive from direct or indirect effects in many organs including the heart. The aim of the present work was to evaluate cardiac sympathetic activity and the expression and activation of two antioxidant proteins: heat shock protein27 (HSP27) and thioredoxin-1 (Trx-1) after voluntary binge ethanol consumption, alone and in combination with MDMA. Material and methods: Adolescent mice received MDMA, ethanol or both. Drinking in the dark (DID) procedure was used as a model of binge. HSP27 expression and phosphorylation at serine 82 (pHSP27), Trx-1 expression, tyrosine hydroxylase (TH) and TH phosphorylated at serine 31 (pTH) were evaluated in adolescent mice 48 h and 7 days after treatments in the right ventricle. TH, HSP27 expression and phosphorylation and Trx-1 expression were measured by quantitative blot immunolabeling using specific antibodies. Key findings: The expression of HSP27, pHSP27, Trx-1, total TH and pTH in the right ventricle was increased after binge ethanol or MDMA alone. In addition, the combination of binge ethanol + MDMA enhanced TH expression and phosphorylation versus their individual administration. Significance: These results indicate that this combination could produce higher activation of sympathetic pathways, which could trigger an increased cell stress. On the other hand, increased HSP27, pHSP27 and Trx-1 expression in the right ventricle by ethanol + MDMA could be a protective mechanism to reduce the adverse effects of oxidative stress caused by both drugs of abuse. The funders of this research have been the Spanish Ministry of Economy and Innovation and FEDER (SAF/FEDER 2013-49076-P, SAF2017-85679-R and SAF2013-41761-R), the Spanish Ministry of Health, Social Affairs and Equality (PNSD 2014-020) and Instituto de Salud Carlos III (Red Temática de Investigación Cooperativa en Salud -ISCIII-FEDER- RETIC-Trastornos Adictivos RTA, RD12/0028/0003 and RD12/0028/0024).

Morphine has been shown to increase the expression of brain-derived neurotrophic factor (BDNF) in the brain. However, little is known about the effect of conditioned naloxone-precipitated morphine withdrawal on BDNF and its precursor protein, proBDNF. We used the conditioned-place aversion (CPA) paradigm to evaluate the role of corticotropin-releasing factor (CRF)/CRF1 receptor signalling on the BDNF expression and corticosterone plasma levels after CPA expression and extinction. Male mice were rendered dependent on morphine and injected acutely with naloxone before paired to confinement in a naloxone-associated compartment. The expression of BDNF and proBDNF in the dentate gyrus (DG) and basolateral amygdala (BLA) was measured in parallel with the corticosterone plasma levels with and without CRF1 receptor blockade. Mice subjected to conditioned naloxone-induced morphine-withdrawal showed an increased expression of BDNF (in DG and BLA) in parallel with an enhancement of corticosterone plasma levels. These results demonstrated that BDNF expression together with the increased activity of hypothalamic-pituitary-adrenocortical (HPA) axis are critical to the acquisition of aversive memory. However, we have observed a decrease in corticosterone plasma levels and BDNF expression after CPA extinction reaffirming the importance of BDNF in the maintenance of aversive memory. In addition, the pre- treatment with the CRF1 receptor antagonist CP-154,526 before naloxone conditioning session impaired morphine withdrawal-induced aversive memory acquisition, the increased corticosterone plasma levels and the expression of BDNF observed after CPA expression in the DG and BLA. Altogether present results suggesting a clear connexion between HPA axis and BDNF in the formation and extinction of aversive memory.

Accumulating evidence indicates that dopamine (DA) D3 receptor (DAD3R) antagonists appear highly promising in attenuating cocaine reward and relapse in preclinical models of addiction. In the present study, we investigated the effects of the selective DAD3R antagonist SB-277011-A on the reinstatement of cocaine-induced conditioned place preference (CPP) produced by a priming dose of cocaine, by social defeat stress and by two kinds of physiological stressors (restraint and tail pinch) in male adult mice. We also explored reinstatement-related plasma corticosterone levels (as marker of stress response) and the effects of blocking DAD3R. Administration of SB-277011-A (24 or 48 mg/kg i.p.) did not modify conditioned reinstatement of cocaine seeking triggered by cocaine prime. By contrast, we found that the vulnerability to reinstatement of the CPP of defeated animals that have undergone CPP extinction was abolished by the DAD3R antagonist (24 mg/kg) given 30 min before the test session. Reactivation of the CPP response produced by physiological stress stimuli was also attenuated by SB-277011-A (48 mg/kg i.p.). On the other hand, the blockade of DAD3R significantly prevented the increased corticosterone release during reinstatement of cocaine-induced CPP that was seen in social defeated animals, in mice suffering physiological stress and after cocaine prime. Present results demonstrate a modulation by DAD3R of the reactivation of the incentive value of cocaine-associated cues induced by social and physiological stress stimuli, which was associated to a glucocorticoid-dependent mechanism. Our results also point to a possible potential therapeutic use of selective DAD3R antagonists for the prevention of stress-induced cocaine-seeking and relapse.

The pharmacokinetic of deflazacort after intravenous and oral administration and the effect of erythromycin on the disposition of deflazacort in rabbits were investigated. A parallel study was carried out in twelve rabbits. The plasma concentration-time profiles of deflazacort were determined after intravenous and oral administration of single dosages of 5 mg/kg in the presence and absence (baseline) of multiple dose erythromycin regimens. Plasma levels of 21-desacetyldeflazacort were determined by HPLC. Plasma concentration-time curves were analysed by compartmental pharmacokinetic and non-compartmental methods. The t½z values following intravenous and oral administration were 3.67 and 4.96 h, respectively. The apparent volume of distribution at steady state (Vss) was 4.08 ± 0.31 L/kg, this value indicates that deflazacort is widely distributed into the extravascular tissues. Moreover, bioavailability after oral administration of deflazacort (F = 87.48 %) was high. Pharmacokinetic analysis after both routes of administration revealed a significant reduction in total body clearance, a significant increase in mean residence time, half-life and plasma concentrations of the steroid in the presence of multiple dose erythromycin. The results indicated the influence of the erythromycin on deflazacort disposition, which is consistent with a pharmacokinetic-type interaction in the elimination of the drug from the body. Moreover this interaction should be considered to avoid adverse effects when using both drugs concomitantly.