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The cognitive and behavioral effects of D-amphetamine and nicotine sensitization in adult zebrafish.Psychopharmacology Aug 2021Zebrafish are growing in use as a model for understanding drug dependence and addiction. Sensitization paradigms have been a useful tool in identifying mechanisms...
BACKGROUND
Zebrafish are growing in use as a model for understanding drug dependence and addiction. Sensitization paradigms have been a useful tool in identifying mechanisms involved in drug-induced behavioral and neurological changes, but in zebrafish have tended to focus on locomotor, rather than cognitive, endpoints.
METHODS
Here, we used a novel method, the FMP Y-maze, which measures continuous performance through a series of repeated binary choices (L vs R), to establish a model for assessing parameters associated with psychostimulant-induced behavioral and cognitive sensitization in adult zebrafish.
RESULTS
Repeat, intermittent exposure to d-amphetamine (AMPH) for 14 days increased alternations (LRLR) in the maze, suggesting improved working memory, which was enhanced further following drug challenge after a short withdrawal period, suggesting behavioral sensitization. However, this cognitive enhancement coincided with a reduction in the use of other exploration strategies, hypolocomotion, and inhibition of cognitive flexibility. Like AMPH, exposure to nicotine (NIC) increased alternations following drug challenge after chronic treatment. Repeat NIC exposure appeared to induce both cognitive and psychomotor sensitization, as evidenced by increased working memory performance (alternations) and locomotor activity, without negatively impacting other search strategies or cognitive flexibility.
CONCLUSION
Chronic treatment with AMPH or NIC boosts cognitive performance in adult zebrafish. Cognitive sensitization occurred with both drugs, resulting in enhanced working memory; however, repeat AMPH exposure, following a withdrawal period, resulted in inhibited cognitive flexibility, an effect not evident with repeat NIC exposure. Cognitive and behavioral sensitization paradigms in zebrafish could serve as a useful tool for assessing cognitive states which result in cognitive enhancing or impairing effects of drugs.
Topics: Age Factors; Animals; Central Nervous System Stimulants; Cognition; Dextroamphetamine; Female; Locomotion; Male; Nicotine; Zebrafish
PubMed: 33963883
DOI: 10.1007/s00213-021-05844-5 -
Lakartidningen Jan 2016Amphetamine dependence is relatively common in Sweden and it is the most frequently used substance among patients with intravenous drug abuse. Current treatment options... (Review)
Review
Amphetamine dependence is relatively common in Sweden and it is the most frequently used substance among patients with intravenous drug abuse. Current treatment options are limited but recently substitution therapy with psychostimulant medication has been evaluated in several clinical trials. Such treatment is controversial in Sweden, perhaps due to the failure of experimental prescription of psychostimulants in the 1960s. Recent clinical trials however indicate that structured treatment programs with psychostimulants might have positive effects, although the results are inconsistent and the evidence base is still limited. Future research is needed in order to determine the potential role of substitution therapy for amphetamine dependence in clinical practice.
Topics: Amphetamine-Related Disorders; Attention Deficit Disorder with Hyperactivity; Central Nervous System Stimulants; Dextroamphetamine; History, 20th Century; Humans; Legislation, Drug; Methylphenidate; Sweden
PubMed: 26756343
DOI: No ID Found -
Public Health Reports (Washington, D.C.... Jan 1960
Topics: Amphetamine; Amphetamines; Humans
PubMed: 13823458
DOI: No ID Found -
Behavioural Pharmacology Oct 2019Individuals with attention-deficit/hyperactivity disorder tend to make risker choices during probabilistic-discounting procedures. Thus, how common...
Individuals with attention-deficit/hyperactivity disorder tend to make risker choices during probabilistic-discounting procedures. Thus, how common attention-deficit/hyperactivity disorder medications affect probabilistic discounting is of interest. In general, d-amphetamine increases risk-taking while atomoxetine has produced mixed effects in rats. Results from previous studies may result from genetic factors. Lewis and F344 rats have neurochemical differences that may be relevant to probabilistic discounting and how drugs affect such behavior. In this study, we evaluated dose-dependent effects of d-amphetamine and atomoxetine on probabilistic discounting of Lewis and F344. Male Lewis and F344 chose between one food pellet delivered 100% of the time and three food pellets delivered following decreasing probabilities of delivery (i.e. 100%, 66.7%, 33.3%, 16.5%, and 8.25%). Saline, d-amphetamine (0.1-1.8 mg/kg), and atomoxetine (0.1-7.8 mg/kg) were tested acutely. Lewis and F344 did not differ in choice at baseline. d-Amphetamine increased risky choice for both rat strains at low-to-moderate doses, although it did so at a lower dose (0.1 and 0.3 mg/kg) for F344 as compared to Lewis (0.3 mg/kg only). At high doses (1.0 and 1.8 mg/kg), d-amphetamine disrupted choice, increased frequencies of omitted trials, and reduced reinforcer sensitivity. Although atomoxetine increased frequencies of omitted trials at high doses (5.6 and 7.8 mg/kg), it had no effect on probabilistic discounting for either rat strain. Although Lewis and F344 differ in various types of impulsivity (i.e. motor, choice), with Lewis being the more impulsive of the two, the present results suggest that Lewis and F344 do not differ in risk-based decision-making. Effects of d-amphetamine on probabilistic discounting may be biology-dependent and differ from effects of atomoxetine.
Topics: Animals; Atomoxetine Hydrochloride; Choice Behavior; Conditioning, Operant; Decision Making; Dextroamphetamine; Impulsive Behavior; Male; Rats; Rats, Inbred F344; Rats, Inbred Lew; Reinforcement Schedule; Reinforcement, Psychology; Risk-Taking
PubMed: 31503070
DOI: 10.1097/FBP.0000000000000500 -
Forensic Toxicology Jul 2023Lisdexamfetamine (LDX), which is used for the treatment of attention-deficit/hyperactivity disorder and narcolepsy, is composed of L-lysine attached to dextroamphetamine...
PURPOSE
Lisdexamfetamine (LDX), which is used for the treatment of attention-deficit/hyperactivity disorder and narcolepsy, is composed of L-lysine attached to dextroamphetamine (d-amphetamine). In this article, we report a forensic autopsy case in which prescription drugs were unknown at autopsy. While amphetamine was detected, methamphetamine could not be detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in any of samples collected. Thus, we aimed to quantify LDX concentrations in autopsy samples and to prove that the amphetamine detected in this case was due to metabolized LDX.
METHODS
Femoral vein blood, cardiac whole blood, urine, and gastric content samples were taken at autopsy for toxicological analysis. Qualitative and quantitative analyses were performed using LC-MS/MS. In addition, optical isomer separation for the amphetamine detected was conducted. The stability of LDX in whole blood and urine was also examined at three different temperatures.
RESULTS
The concentrations of LDX were < 4.00, 30.9, and 4.42 ng/mL in whole blood, urine, and gastric content samples, respectively. The concentrations of amphetamine were 329, 510, 2970, and 915 ng/mL in femoral vein blood, heart whole blood, urine, and gastric contents, respectively. The amphetamine detected in this case was identified to be only d-amphetamine by optical isomer separation. The d-amphetamine detected was considered to be derived from LDX. Stability experiments revealed that LDX in whole blood decreased at ambient temperature.
CONCLUSIONS
The results in the present case report may be useful in interpreting whether or not the amphetamine detected in a cadaver is a metabolite of LDX.
Topics: Humans; Lisdexamfetamine Dimesylate; Amphetamine; Dextroamphetamine; Autopsy; Chromatography, Liquid; Tandem Mass Spectrometry; Prodrugs; Cadaver
PubMed: 36562920
DOI: 10.1007/s11419-022-00654-6 -
Biological Psychiatry. Cognitive... May 2024While the exploration of serotonergic psychedelics as psychiatric medicines deepens, so does the pressure to better understand how these compounds act on the brain. (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
While the exploration of serotonergic psychedelics as psychiatric medicines deepens, so does the pressure to better understand how these compounds act on the brain.
METHODS
We used a double-blind, placebo-controlled, crossover design and administered lysergic acid diethylamide (LSD), 3,4-methylenedioxymethamphetamine (MDMA), and d-amphetamine in 25 healthy participants. By using spectral dynamic causal modeling, we mapped substance-induced changes in effective connectivity between the thalamus and different cortex types (unimodal vs. transmodal) derived from a previous study with resting-state functional magnetic resonance imaging data. Due to the distinct pharmacological modes of action of the 3 substances, we were able to investigate specific effects mainly driven by different neurotransmitter systems on thalamocortical and corticothalamic interactions.
RESULTS
Compared with placebo, all 3 substances increased the effective connectivity from the thalamus to specific unimodal cortices, whereas the influence of these cortices on the thalamus was reduced. These results indicate increased bottom-up and decreased top-down information flow between the thalamus and some unimodal cortices. However, for the amphetamines, we found the opposite effects when examining the effective connectivity with transmodal cortices, including parts of the salience network. Intriguingly, LSD increased the effective connectivity from the thalamus to both unimodal and transmodal cortices, indicating a breach in the hierarchical organization of ongoing brain activity.
CONCLUSIONS
The results advance our knowledge about the action of psychedelics on the brain and refine current models aiming to explain the underlying neurobiological processes.
Topics: Humans; Lysergic Acid Diethylamide; N-Methyl-3,4-methylenedioxyamphetamine; Thalamus; Male; Double-Blind Method; Adult; Magnetic Resonance Imaging; Hallucinogens; Dextroamphetamine; Cross-Over Studies; Female; Cerebral Cortex; Young Adult; Neural Pathways; Connectome
PubMed: 37532129
DOI: 10.1016/j.bpsc.2023.07.010 -
Pharmacology, Biochemistry, and Behavior May 2021It is commonly believed that drugs, including stimulants, are used recreationally because of their ability to induce pleasurable subjective effects. However,...
BACKGROUND
It is commonly believed that drugs, including stimulants, are used recreationally because of their ability to induce pleasurable subjective effects. However, recreational drug use sometimes occurs in the absence of positive subjective effects, suggesting that other factors contribute. Here, we examine the extent to which the direct subjective effects of amphetamine, a commonly misused stimulant, predict subsequent choice of the drug vs placebo.
METHODS
Healthy adults (N = 112) participated in a five-session amphetamine choice study. On the first four sessions, participants sampled either 20 mg d-amphetamine or placebo in color-coded capsules two times each. On the fifth session, they chose which color (d-amphetamine or placebo) they preferred. We examined the choice of drug vs placebo in relation to demographic characteristics, baseline mood states, personality and subjective and cardiovascular responses to acute administration of the drug.
RESULTS
Eighty-one participants chose amphetamine (Choosers) while 31 chose placebo (Non-choosers). Overall, amphetamine produced typical stimulant-like effects on subjective questionnaires, and it elevated heart rate and blood pressure vs placebo. Choosers reported greater positive mood, elation and stimulant-like effects following amphetamine compared to Non-choosers. The Choosers also exhibited a greater increase in systolic blood pressure, but not heart rate. The groups did not differ on demographic characteristics, mood states before drug administration or personality.
CONCLUSIONS
These findings support the idea that pleasurable subjective responses to amphetamine, including positive mood, elation, and stimulant-like effects influence behavioral choice of the drug.
Topics: Adult; Affect; Arousal; Blood Pressure; Central Nervous System Stimulants; Choice Behavior; Dextroamphetamine; Female; Healthy Volunteers; Heart Rate; Humans; Male; Personality; Recreational Drug Use; Young Adult
PubMed: 33675838
DOI: 10.1016/j.pbb.2021.173158 -
Drug Design, Development and Therapy 2014Recent studies have promised that lisdexamfetamine (LDX) is effective in the treatment of adults with attention-deficit hyperactivity disorder (ADHD). (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Recent studies have promised that lisdexamfetamine (LDX) is effective in the treatment of adults with attention-deficit hyperactivity disorder (ADHD).
OBJECTIVES
This systematic review was undertaken to summarize LDX efficacy, acceptability, and tolerability in adult ADHD. All randomized controlled trials (RCTs) of lisdexamfetamine compared with placebo were included for synthesis. Clinical trials published between January 1991 and January 2014 were evaluated.
METHODS
The database of MEDLINE(®), EMBASE™, CINAHL(®), PsycINFO(®) and Cochrane Controlled Trials Register were searched in January 2014. Studies were also searched in ClinicalTrials.gov and the EU Clinical Trials Register database. Study eligibility criteria, participants, and interventions were considered. All RCTs of LDX vs placebo reporting final results of: 1) severity of ADHD symptoms and executive function deficit, 2) response or remission rates, 3) overall discontinuation rate, or 4) discontinuation rate due to adverse events were included. The language of the papers was not restricted. All abstracts of studies gathered from the database were examined. After excluding irrelevant trials, the full text version of relevant studies were assessed and extracted for outcomes of interest. Examination of risks of bias, based on the Cochrane bias assessment, was carried out. The efficacy outcomes consisted of the mean end point or change scores for ADHD rating scales, the response rate, and the remission rate. The overall discontinuation rate and the discontinuation rate due to adverse events were measured for acceptability and tolerability, respectively. A random effect model was applied for the synthesis of relative risks (RRs), and weighted mean differences or standardized mean differences (SMDs) with 95% confidence intervals (CIs).
RESULTS
A total of 806 final study or safety participants were included. The dosage of lisdexamfetamine was 30 to 70 mg/day. The pooled mean scores of mean change and mean end point scores between LDX- and placebo-treated groups also had a significant difference (SMD [95% CI] of -0.97 [-1.15, -0.78], I(2)=18%). The pooled response rates for adult ADHD between the two groups had a significant difference (RR [95% CI] of 1.99 [1.50, 2.63], I(2)=0%). Based on the Behavior Rating Inventory of Executive Function - Adult version (BRIEF-A), the pooled end point mean scores for the Global Executive Composite (GEC) for the LDX-treated groups was greater than that of placebo-treated groups (MD [95% CI] of -9.20 [-14.11, -4.29], I(2)=34%). The pooled overall discontinuation rates between the two groups had no significant difference (RR [95% CI] of 0.82 [0.59, 1.14], I(2)=0%). Similarly, the pooled discontinuation rates due to adverse events between the two groups was not significantly different (RR [95% CI] of 1.77 [0.71, 4.40], I(2)=0%).
CONCLUSION
The number of included studies was limited (five RCTs), but based on this meta-analysis, LDX is efficacious and well tolerated in the treatment of adult ADHD. Additionally, it also improved the executive function deficits in this population. However, its acceptability is no higher than placebo. These findings should be carefully interpreted and considered as preliminary outcomes. To confirm these results, further studies are warranted. LDX is a viable alternative psychostimulant for adult ADHD.
Topics: Attention Deficit Disorder with Hyperactivity; Databases, Factual; Dextroamphetamine; Humans; Lisdexamfetamine Dimesylate; Placebos; Registries
PubMed: 25336914
DOI: 10.2147/DDDT.S68393 -
Current Neuropharmacology 2020To systematically review the literature on the therapeutic use of amphetamine, lisdexamfetamine and methylphenidate in elderly population with and without dementia.
OBJECTIVE
To systematically review the literature on the therapeutic use of amphetamine, lisdexamfetamine and methylphenidate in elderly population with and without dementia.
METHODS
We conducted two researches on the PubMed, Scopus and Embase using the keywords ("elderly") AND ("amphetamine" OR "methylphenidate" OR "lisdexamfetamine") and then ("Alzheimer" OR "dementia") AND ("amphetamine" OR "methylphenidate" OR "lisdexamfetamine").
RESULTS
Twenty-nine papers met all the eligibility criteria. The results are encouraging as 81.5% of the studies showed clinical improvement of the investigated condition.
CONCLUSION
Amphetamines and methylphenidate are probably effective strategies for different conditions in the elderly population. However, further studies are needed to provide more robust evidence on efficacy, dosage and safety for this population.
Topics: Aged; Amphetamine; Dementia; Depressive Disorder, Major; Humans; Lisdexamfetamine Dimesylate; Methylphenidate
PubMed: 31660835
DOI: 10.2174/1570159X17666191010093021 -
NTP CERHR MON Jul 2005The National Toxicology Program (NTP) Center for the Evaluation of Risks to Human Reproduction (CERHR) conducted an evaluation of the potential for amphetamines to cause... (Review)
Review
The National Toxicology Program (NTP) Center for the Evaluation of Risks to Human Reproduction (CERHR) conducted an evaluation of the potential for amphetamines to cause adverse effects on reproduction and development in humans. Amphetamines evaluated were D- and D,L-amphetamine and methamphetamine. Amphetamine is approved by the U.S. Food and Drug Administration for the treatment of attention deficit hyperactivity disorder (ADHD) in persons over 3 years of age and narcolepsy; methamphetamine is approved for the treatment of ADHD in persons 6 years of age and older and for short-term treatment of obesity. Amphetamines were selected for evaluation because of 1) widespread usage in children, 2) availability of developmental studies in children and experimental animals, and 3) public concern about the effect of this stimulant on child development. The results of this evaluation on amphetamines are published in an NTP-CERHR monograph which includes: 1) the NTP Brief, 2) the Expert Panel Report on the Reproductive and Developmental Toxicity of Methylphenidate, and 3) public comments received on the Expert Panel Report. As stated in the NTP Brief, the NTP reached the following conclusions regarding the possible effects of exposure to methylphenidate on human development and reproduction. First, there is some concern for developmental effects, specifically for potential neurobehavioral alterations, from prenatal amphetamine exposure in humans both in therapeutic and non-therapeutic settings. After prenatal exposure to therapeutic doses of amphetamine, rat pups demonstrated neurobehavioral alterations. Data from human and animal studies were judged insufficient for an evaluation of the effect of amphetamine exposure on growth and other related developmental effects. Second, there is concern for methamphetamine-induced adverse developmental effects, specifically on growth and neurobehavioral development, in therapeutic and non-therapeutic settings. This conclusion is based on evidence from studies in experimental animals that prenatal and postnatal exposures to methamphetamine produce neurobehavioral alterations, small litter size, and low birth weight. Results from studies in humans suggest that methamphetamine may cause low birth weight and shortened gestation, but study confounders such as possible multiple drug usage prevent a definite conclusion. NTP-CERHR monographs are transmitted to federal and state agencies, interested parties, and the public and are available in electronic PDF format on the CERHR web site (http://cerhr.niehs.nih.gov) and in printed text or CD-ROM from the CERHR (National Institute of Environmental Health Sciences, P.O. Box 12233, MD EC-32, Research Triangle Park, NC; fax: 919-316-4511).
Topics: Amphetamine; Animals; Attention Deficit Disorder with Hyperactivity; Behavior, Animal; Central Nervous System Stimulants; Dextroamphetamine; Female; Government Agencies; Government Programs; Humans; Infant, Low Birth Weight; Infant, Newborn; Learning; Litter Size; Memory; Methamphetamine; Narcolepsy; Obesity; Pregnancy; Prenatal Exposure Delayed Effects; Reproduction; Substance-Related Disorders
PubMed: 16130031
DOI: No ID Found