Maternal Deprivation in Rat: Model of Vulnerability to Opiate Addiciton

2009 ◽  
Vol 24 (S1) ◽  
pp. 1-1 ◽  
Author(s):  
V. Dauge

Aims:The concept of individual vulnerability applied to mental pathology involves genetic background and/or environmental context. We studied the impact of environmental factors such as maternal deprivation on the appearance of a vulnerability to addiction. Maternal deprivation represents an early stress, a lack of nursing occurring during a period of intense neuronal development and then could lead to long term brain functioning abnormalities. It has been recently shown that > 900 genes are stably regulated by maternal care in rat.Methods:Pups were separated from their mother and littermate the day after birth 3h/day for 14 days. Place preference and oral auto-administration tests were performed at the adulthood. Opioidergic and dopaminergic systems were studied.Results:We showed that maternal deprivation leads in adult male rats to a hypersensitivity to the rewarding and reinforcing effects of morphine correlated with a basal hypoactivity of the striatal enkephalinergic system. Maternal deprivation did not change oral self-administration behavior of cocaine and alcohol. Adolescent chronic tetrahydrocannabinol exposure suppressed morphine dependence in adult deprived rats.Conclusion:Maternal deprivation represents a highly valuable model to study environmentally triggered inter-individual vulnerability to opiate addiction. The suppression of morphine dependence in adult deprived rats after adolescent chronic tetrahydrocannabinol exposure raise the question of the beneficial effects of cannabis in opiate dependence vulnerability context.

2021 ◽  
Vol 12 ◽  
Author(s):  
Robert W. Seaman Jr ◽  
Gregory T. Collins

Recent estimates suggest increased popularity of the concurrent use of opioids and stimulants, with over 50% of treatment-seeking opioid users reporting regular stimulant use. The goal of the current study was to determine how opioid dependence and withdrawal affect the reinforcing effects of fentanyl, cocaine, and methamphetamine. Male Sprague-Dawley rats were allowed to self-administer fentanyl under a progressive ratio (PR) schedule of reinforcement. Baseline evaluations of reinforcing effectiveness of fentanyl, cocaine, and methamphetamine were determined. Opioid dependence was then established by administering escalating doses of morphine (10–40 mg/kg) twice-daily for four days and subsequently maintained by once-daily injections of 40 mg/kg morphine. To evaluate the impact of opioid dependence and withdrawal on the self-administration of fentanyl, cocaine, and methamphetamine, sessions occurred either 12 or 20 h after the morphine, respectively. During opioid withdrawal, the fentanyl dose-response curve was shifted rightward with an increase in maximal effectiveness, whereas it was shifted rightward with a reduction in maximal effectiveness when evaluated in rats currently dependent on opioids, relative to baseline. The reinforcing effects of cocaine and methamphetamine were unchanged by either condition. The current studies provide direct evidence that the reinforcing effects of fentanyl are increased in opioid-withdrawn rats and reduced in opioid-dependent rats, relative to rats that are not physically dependent on opioids. These findings suggest that motivations to use opioids are dependent on the state of the individual whereas stimulants retain their reinforcing effects regardless of whether the individual is in an opioid-dependent or withdrawn state.


2015 ◽  
Vol 207 (1) ◽  
pp. 72-78 ◽  
Author(s):  
Benedikt Till ◽  
Markus Strauss ◽  
Gernot Sonneck ◽  
Thomas Niederkrotenthaler

BackgroundMedia stories on suicide can increase suicidal ideation, but little is known about variations in media effects with regard to audience vulnerability and story contents.AimsWe investigated the impact of three drama films with suicidal content that varied with regard to the final outcome (suicide completion, mastery of crisis and death by natural causes) and tested the moderating effect of baseline suicidality of the participants on the effects.MethodWithin a laboratory setting, we randomly assigned 95 adults to three film groups. We used questionnaires to analyse the effects of the films on mood, depression, life satisfaction, self-worth, assumed benevolence of the world and suicidality, as well as identification with the protagonist. We stratified the sample into participants with suicidal tendencies above and below the sample median.ResultsThe film that ended with the protagonist's suicide led to a deterioration of mood particularly in individuals with baseline suicidality below the median, who also experienced an increase in self-worth. Participants with stronger suicidal tendencies experienced a rise in suicidality that depended on their level of identification with the protagonist. The film featuring the main character positively coping with his crisis increased life satisfaction particularly among participants with higher suicidal tendencies.ConclusionsThe effects of suicide-related media material seem to vary with individual vulnerability and with type of media portrayal. Individuals with lower vulnerability experience more emotional reactions when exposed to a film culminating in suicide, but individuals with higher vulnerability experience a rise in suicidal tendencies particularly if they identify with the protagonist who died by suicide. In contrast, portrayals of individual mastery of crisis may have beneficial effects in more vulnerable individuals.


2019 ◽  
Author(s):  
Nathaniel P. Stafford ◽  
Theodore N. Kazan ◽  
Colleen M. Donovan ◽  
Erin E. Hart ◽  
Robert C. Drugan ◽  
...  

AbstractOpioid use is a widespread epidemic, and traumatic stress exposure is a critical risk factor in opioid use and relapse. There is a significant gap in our understanding of how stress contributes to heroin use, and there are limited studies investigating individual differences underlying stress reactivity and subsequent stress-induced heroin self-administration. We hypothesized that greater individual vulnerability to stress would predict higher demand for heroin self-administration in a within-subjects rodent model of stress and heroin use comorbidity. Male rats were exposed to inescapable intermittent swim stress and individual biological (corticosterone) or behavioral (open field, social exploration, and forced swim tests) measures were assessed before and after the stress episode. Individual demand for self-administered heroin (0.05 mg/kg/infusion; 12-hour sessions) was assessed using a behavioral economics approach followed by extinction and reinstatement tests triggered by stress re-exposure, non-contingent cue presentations, and yohimbine (0, 1.0, or 2.5 mg/kg). We found that behavioral, biological, and a combination of behavioral and biological markers sampled prior and after the stress episode that occurred weeks before the access to heroin selfadministration predicted the magnitude of individual demand for heroin. Non-contingent presentation of cues, that were previously associated with heroin, reinstated heroin seeking in extinction. For the first time, we show that individual biological response to an ecologically relevant stressor in combination with associated behavioral markers can be used to predict subsequent economic demand for heroin.


Author(s):  
Fatemeh Moinaddini ◽  
Tahereh Haghpanah ◽  
Mohsen Abedini Esfahlani ◽  
Maryam Amirinejad ◽  
Seyed Noureddin Nematollahi-Mahani

Background: Opiate dependence, a great worldwide obstacle, is regularly treated by detoxification via opioid agonists and antagonist administration. However, different effects and severity of detoxification on the male reproductive system have not been evaluated so far. Objectives: Thus, the present study intended to investigate the impact of morphine dependence and detoxification with methadone and/or buprenorphine on sexual behavior and sex hormones in an animal model of opiate dependence. Materials and Methods: sixty-six adult male mice were randomly allocated into six groups of control (ctl40), morphine-dependent (Mrph40) (which received morphine for 40 days), another control (Ctrl80), morphine-dependent (Mrph80) (which received morphine for 80 days), methadone (Mtdn) detoxified, and buprenorphine (Bprn) detoxified groups (n = 11). Different aspects of sexual activities and Sex hormones were assessed at the end of the treatment period. Data were analyzed by ANOVA test and chi-squared test using SPSS version 16 software for Windows. Results: Testosterone level significantly decreased in all treated groups compared with its level in the Ctl40 group. Detoxification with buprenorphine was reduced following 80 days of treatment, the level of testosterone significantly reduced in all treated groups compared to its level in the Ctrl80 group. The highest and lowest levels of FSH were observed in the Bprn group and in the Mrph40 group, respectively, even lower than that of the Mrph80 and Mtdn groups. Either of the treatments has decreased the level of LH when compared with its level in the controls. Various sexual behaviors were differently disturbed in the treated groups. Duration of sexual activity, Mount frequency, ejaculation latency, and sexual activity duration was higher in the Bprn group than the Mtdn group, but the rate of pregnancy was much higher in the Mtdn group. Conclusions: Either Short or long-term dependence on morphine affects the sex hormones and activities. Following detoxification with methadone and/or buprenorphine, various aspects of sexual behaviors were differently altered, which could alert clinicians in detoxification programs.


Author(s):  
Ilma Robo

The treatment of periodontal diseases, mainly of their origin, with the most common clinical manifestation in form of gingival inflammation, is manifold and powerful, including: mechanical therapy, antibiotic, antiseptic and various approaches to treatment, which are recommended to be used within a short period of time. New therapeutic approaches have been proven as alternative treatment to conventional therapy, or in combination with conventional therapies, to reduce the number of periodontopathic pathogens in gingival sulcus. HBOT has a detrimental effect on periodontal microorganisms, as well as beneficial effects on the healing of periodontal tissue, increasing oxygen pressure in gingival pockets. Our study is aimed at reviewing the current published literature on hyperbaric oxygen therapy and focuses on role of HBOT as a therapeutic measure for the individual with periodontal disease in general and for the impact on the recovery of gingival inflammation. HBOT and periodontal treatment together, reduce up to 99% of the gram-negative anaerobic load of subgingival flora. HBOT, significantly reduces subgingival anaerobic flora. Clinical effects in 2-year follow-up of treated patients are sensitive. Reduction of gingival hemorrhage indexes, depth of peritoneum, plaque index, occurs in cases of combination of HBOT and detraction. Reduced load persists up to 2 months after therapy. The significant increase in connective tissue removal starts at the end of 2nd week, to achieve the maximum in week 3-6 of application. HBOT used for re-implantation, stimulates the healing of periodontal membrane, pulp, prevents root resorption, healing of periodontal lining tissues. HBOT, significantly reduces the hemorrhage index with 1.2 value difference, 0.7mm probe depth, reduces gingival fluid by 2. HGH exposure is increased by gingival blood flow, with a difference of 2 in measured value. The therapeutic effects of HBOT in the value of the evaluation index can be saved up to 1-year post treatment.


2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
C Dupré ◽  
N Barth ◽  
A El Moutawakkil ◽  
F Béland ◽  
F Roche ◽  
...  

Abstract Background Few previous cohorts have studied the different type of physical activities and the degree of cognitive decline. The objective of this work was to analyze the leisure, domestic and professional activities with mild and moderate cognitive disorders in older people living in community. Methods The study used data from the longitudinal and observational study, FrèLE (FRagility: Longitudinal Study of Expressions). The collected data included: socio-demographic variables, lifestyle, and health status (frailty, comorbidities, cognitive status, depression). Cognitive decline was assessed by using: MMSE (Mini-Mental State Examination) and MoCA (Montreal Cognitive Assessment). MoCA was used with two cut-offs (26 and 17) so as to define mild and moderate cognitive disorders Physical activity was assessed by the PASE (Physical Activity Scale for the Elderly), structured in three sections: leisure, domestic and professional activities. Spline and proportional hazards regression models (Cox) were used to estimate the risk of cognitive disorders. Results At baseline, 1623 participants were included and the prevalence of cognitive disorders was 6.9% (MMSE) and 7.2% (MoCA), mild cognitive disorders was 71.3%. The mean age was 77 years, and 52% of the participants were women. After a 2 years long follow-up, we found 6.9% (MMSE) and 6% (MoCA) cognitive disorders on participants. Analyses showed that domestic activities were associated to cognitive decline (HR = 0.52 [0.28-0.94] for MMSE and HR = 0.48 [0.28-0.80] for MoCA). No association were found with leisure and professional activities, and no spline were significant with mild cognitive disorders. Conclusions Analysis showed a relationship between cognitive disorders and type of physical activity, thanks to the use of specific questionnaire of elderly and two global test of cognition. These findings will contribute to the debate on the beneficial effects of physical activity on cognition. Key messages This work allowed to compare two test of cognition and their link with physical activity. It contributes to the debate on the beneficial effects of physical activity on cognition. The work allowed us to see the effect of the different types of physical activity and the impact of the statistical method on the results.


Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1751
Author(s):  
Rosa María Tremiño ◽  
Teresa Real-Herraiz ◽  
Viviana Letelier ◽  
José Marcos Ortega

One of the most popular ways to lessen the impact of the cement industry on the environment consists of substituting clinker by additions. The service life required for real construction elements is generally long, so it would be interesting to obtain information about the effects of new additions after a hardening period of several years. Analyzed here are the effects of the incorporation of volcanic ashes, coming from Calbuco volcano’s last eruption (Chile), as clinker replacement, in the durability and pore structure of mortars, after approximately 4 hardening years (1500 days), in comparison with reference specimens without additions. The substitution percentages of clinker by volcanic powder studied were 10% and 20%. The microstructure was characterized with mercury intrusion porosimetry and impedance spectroscopy. In order to evaluate the pozzolanic activity of the volcanic powder after 1500 days, differential thermal analyses were performed. Water absorption after immersion, steady-state diffusion coefficient and length change were also studied. In accordance with the results obtained, the 10% and 20% substitution of clinker by volcanic powder from the Calbuco volcano showed beneficial effects in the mortars after 4 years, especially regarding the microstructure and chloride diffusion, without noticeable influence in their water absorption.


Biochar ◽  
2021 ◽  
Author(s):  
Ngitheni Winnie-Kate Nyoka ◽  
Ozekeke Ogbeide ◽  
Patricks Voua Otomo

AbstractTerrestrial and aquatic ecosystems are increasingly threatened by pesticide pollution resulting from extensive use of pesticides, and due to the lack of regulatory measures in the developing world, there is a need for affordable means to lessen environmental effects. This study aimed to investigate the impact of biochar amendment on the toxicity of imidacloprid to life-cycle parameters and biomarker responses of the earthworm Eisenia fetida. E. fetida was exposed to 10% biochar-amended and non-amended OECD artificial soils spiked with 0, 0.75, 1.5, 2.25 and 3 mg imidacloprid/kg for 28 days. An LC50 of 2.7 mg/kg was only computed in the non-amended soil but not in the biochar-amended soil due to insignificant mortality. The EC50 calculated in the non-amended soil (0.92 mg/kg) for reproduction (fertility) was lower than the one computed in the biochar amended (0.98 mg/kg), indicating a decrease in toxicity in the biochar-amended substrate. Significant weight loss was observed at the two highest imidacloprid treatments in the non-amended soil and only at the highest treatment in the biochar-amended substrate, further highlighting the beneficial effects of biochar. Catalase activity decreased significantly at the two highest concentrations of non-amended soil. Yet, in the amended soil, the activity remained high, especially in the highest concentration, where it was significantly higher than the controls. This indicated more severe oxidative stress in the absence of biochar. In all non-amended treatments, there was a significant acetylcholinesterase inhibition, while lower inhibition percentages were observed in the biochar-amended soil. In most endpoints, the addition of biochar alleviated the toxic effects of imidacloprid, which shows that biochar has the potential to be useful in soil remediation. However, there is still a need for field studies to identify the most effective application rate of biochar for land application.


Author(s):  
Ewa Zwierzyńska ◽  
Agata Krupa-Burtnik ◽  
Bogusława Pietrzak

Abstract Background Retigabine belongs to the novel generation of antiepileptic drugs but its complex mechanism of action causes that the drug might be effective in other diseases, for instance, alcohol dependence. It is known that ethanol abuse impaired the function of brain structures associated with memory and learning such as the hippocampus. In our previous study, retigabine reduced hippocampal changes induced by ethanol in the EEG rhythms in rabbits. This study is focused on the impact of retigabine on memory processes in male rats receiving alcohol. Methods Memory was evaluated in various experimental models: Morris water maze, Contextual, and Cued Fear Conditioning tests. Retigabine was administered for 3 weeks directly to the stomach via oral gavage at a dose of 10 mg/kg. Rats received also 20% ethanol (5 g/kg/day in two doses) via oral gavage for 3 weeks and had free access to 5% ethanol in the afternoon and at night. Morris water maze was performed after 1 and 3 weeks of ethanol administration and after 1 week from the discontinuation of ethanol administration. Contextual and Cued Fear Conditioning tests were carried out after 24 h and 72 h of alcohol discontinuation. Results The drug significantly decreased ethanol-induced memory disturbances during alcohol administration as well as slightly improved learning processes after the discontinuation of ethanol administration. Conclusions This beneficial effect of retigabine-ethanol interaction on memory may be a relevant element of the drug’s impact on the development of addiction.


2021 ◽  
Vol 43 (4) ◽  
Author(s):  
Agnieszka Ostrowska ◽  
Maciej T. Grzesiak ◽  
Tomasz Hura

AbstractSoil drought is a major problem in plant cultivation. This is particularly true for thermophilic plants, such as maize, which grow in areas often affected by precipitation shortage. The problem may be alleviated using plant growth and development stimulators. Therefore, the aim of the study was to analyze the effects of 5-aminolevulinic acid (5-ALA), zearalenone (ZEN), triacontanol (TRIA) and silicon (Si) on water management and photosynthetic activity of maize under soil drought. The experiments covered three developmental stages: three leaves, stem elongation and heading. The impact of these substances applied during drought stress depended on the plant development stage. 5-ALA affected chlorophyll levels, gas exchange and photochemical activity of PSII. Similar effects were observed for ZEN, which additionally induced stem elongation and limited dehydration. Beneficial effects of TRIA were visible at the stage of three leaves and involved leaf hydration and plant growth. A silicon preparation applied at the same developmental stage triggered similar effects and additionally induced changes in chlorophyll levels. All the stimulators significantly affected transpiration intensity at the heading stage.


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