Separation of short and medium-chain fatty acids using capillary electrophoresis with indirect photometric detection: Part I: Identification of fatty acids in rat feces.

Short and medium-chain fatty acids (SMCFAs) are known as essential metabolites found in gut microbiota that function as modulators in the development and progression of many inflammatory conditions as well as in the regulation of cell metabolism. Currently, there are few simple and low-cost analytical methods available for the determination of SMCFA. This report focuses on SMCFA analysis utilizing CE with indirect photometric detection (CE-IPD).

Sex-dependent regulation of social reward by oxytocin receptors in the ventral tegmental area.

Social reward is critical for social relationships, and yet we know little about the characteristics of social interactions that are rewarding or the neural mechanisms underlying that reward. Here, we investigate the sex-dependent role of oxytocin receptors within the ventral tegmental area (VTA) in mediating the magnitude and valence of social reward. Operant and classical conditioning tests were used to measure social reward associated with same-sex social interactions.

ARC and BDNF expression after cocaine self-administration or cue-induced reinstatement of cocaine seeking in adolescent and adult male rats.

Recreational drug use peaks during adolescence. Our research with adolescent vs adult male rats, however, shows that rats taking cocaine as adolescents have lower levels of cue-induced reinstatement of drug-seeking than adults, despite similar levels of intravenous (i.v.

Sex-dependent regulation of social reward by oxytocin: an inverted U hypothesis.

The rewarding properties of social interactions are essential for the expression of social behavior and the development of adaptive social relationships. Here, we review sex differences in social reward, and more specifically, how oxytocin (OT) acts in the mesolimbic dopamine system (MDS) to mediate the rewarding properties of social interactions in a sex-dependent manner. Evidence from rodents and humans suggests that same-sex social interactions may be more rewarding in females than in males.

Role of oxytocin in the ventral tegmental area in social reinforcement.

The rewarding properties of social interactions play a critical role in the development and maintenance of social relationships, and deficits in social reward are associated with various psychiatric disorders. In the present study, we used a novel Operant Social Preference (OSP) task to investigate the reinforcing properties of social interactions under conditions of high or low reward value, and high or low behavioral effort in male Syrian hamsters. Further, we investigated the role of oxytocin (OT) in a key structure of the mesolimbic reward system, the ventral tegmental area (VTA), in mediating the reinforcing properties of social interaction.

Abstinence environment contributes to age differences in reinstatement of cocaine seeking between adolescent and adult male rats.

Rationale: Extinction responding and cue-induced reinstatement of cocaine seeking after 60-days of forced abstinence are attenuated in male rats that self-administered cocaine during adolescence, compared with adults. Given that environmental enrichment during abstinence decreases reinstatement among adults, a possible explanation for attenuated reinstatement among adolescents is that standard pair-housing in prior studies creates a more stimulating environment for younger rats.

Objective: Therefore, we tested whether standard pair-housing is necessary for the attenuated reinstatement among adolescents by determining whether an impoverished environment during abstinence would increase reinstatement among adolescents, up to adult levels.

A novel operant task to assess social reward and motivation in rodents.

Background: Social reward plays a critical role in the development of beneficial social relationships, and disorders of the mechanisms controlling social reward are involved in the etiology of many psychiatric diseases.

New Method: We present a novel operant social preference task to quantify social reward in rodents using an apparatus with three chambers separated by one-way vertical-swing doors. The experimental animal is placed in the larger chamber while the two smaller chambers either remain empty or contain a stimulus animal or other potential reward stimulus.

Altered sucrose self-administration following injection of melanocortin receptor agonists and antagonists into the ventral tegmental area.

Rationale And Objectives: Alpha-melanocyte stimulating hormone (αMSH) and agouti-related protein (AgRP) are antagonistic neuropeptides that play an important role in the control of feeding and body weight through their central actions on the melanocortin-3 and melanocortin-4 receptors. Increasing evidence indicates that αMSH and AgRP can interact with the mesolimbic dopamine system to regulate feeding as well as other behaviors. For example, we have shown previously that injection of melanocortin receptor agonists and antagonists into the ventral tegmental area (VTA) alters both normal home-cage feeding and the intake of sucrose solutions, but it remains unknown whether αMSH and AgRP can also act in the VTA to affect reward-related feeding.

A Comparison of Internal Dispositions and Career Trajectories after Collaborative versus Apprenticed Research Experiences for Undergraduates.

Undergraduate research experiences confer benefits on students bound for science, technology, engineering, and mathematics (STEM) careers, but the low number of research professionals available to serve as mentors often limits access to research. Within the context of our summer research program (BRAIN), we tested the hypothesis that a team-based collaborative learning model (CLM) produces student outcomes at least as positive as a traditional apprenticeship model (AM). Through stratified, random assignment to conditions, CLM students were designated to work together in a teaching laboratory to conduct research according to a defined curriculum led by several instructors, whereas AM students were paired with mentors in active research groups.

A role for the prefrontal cortex in heroin-seeking after forced abstinence by adult male rats but not adolescents.

Adolescent drug abuse is hypothesized to increase the risk of drug addiction. Yet male rats that self-administer heroin as adolescents show attenuated drug-seeking after abstinence, compared with adults. Here we explore a role for neural activity in the medial prefrontal cortex (mPFC) in age-dependent heroin-seeking.

Attenuated effects of experimenter-administered heroin in adolescent vs. adult male rats: physical withdrawal and locomotor sensitization.

Objectives: Early onset of heroin use during adolescence might increase chances of later drug addiction. Prior work from our laboratory suggests, however, that adolescent male rats are actually less sensitive than adults to some enduring effects of heroin self-administration. In the present study, we tested two likely correlates of sensitivity to behavioral reinforcement in rats: physical withdrawal and locomotor sensitization.

New perspectives on adolescent motivated behavior: attention and conditioning.

Adolescence is a critical transition period, during which fundamental changes prepare the adolescent for becoming an adult. Heuristic models of the neurobiology of adolescent behavior have emerged, promoting the central role of reward and motivation, coupled with cognitive immaturities. Here, we bring focus to two basic sets of processes, attention and conditioning, which are essential for adaptive behavior.

Heroin self-administration and reinstatement of heroin-seeking in adolescent vs. adult male rats.

Rationale: Heroin abuse is prevalent among teenagers, and early onset drug use might predict long-term drug dependence. However, adolescent sensitivity to drug reinforcement has not been explored thoroughly in animal models.

Objectives: This study aimed to compare intravenous (i.

A high fructose diet does not affect amphetamine self-administration or spatial water maze learning and memory in female rats.

High energy diets can have a detrimental effect on brain plasticity. For example, a high fructose diet impairs spatial memory in male rats. The aim of the present study was to determine whether a high fructose diet impairs another form of learning and memory: drug reinforcement learning.

Time-dependent increases in cue-induced reinstatement of sucrose seeking after sucrose self-administration in adolescence.

Previously we reported that time-dependent increases in cue-induced reinstatement of cocaine seeking were attenuated in rats self-administering cocaine as adolescents, compared with adults (Li and Frantz (2009)). Now using sucrose self-administration, we report time-dependent increases in cue-induced reinstatement of sucrose seeking are similar across age groups, suggesting that age differences in reinstatement of cocaine seeking depend on specific effects of cocaine, not a compromised ability among younger rats to associate cues with rewards.

Attenuated incubation of cocaine seeking in male rats trained to self-administer cocaine during periadolescence.

Rationale And Objectives: Although onset of drug use during adolescence appears to increase long-term vulnerability to drug dependence in humans, relatively little is known about extinction and reinstatement of drug seeking after periadolescent onset of drug self-administration in laboratory animals. Furthermore, although cue-induced reinstatement of cocaine seeking increases progressively during abstinence from cocaine self-administration in adult subjects, this "incubation of cocaine craving" remains unexplored after adolescent drug intake in animal models.

Materials And Methods: We allowed periadolescent (postnatal day (PND) 35 at start) and adult (PND 83-95 at start) male Wistar rats to self-administer cocaine (0.

Age-dependent morphine intake and cue-induced reinstatement, but not escalation in intake, by adolescent and adult male rats.

Despite increasing rates of opioid abuse by human adolescents, few laboratory experiments address adolescent vulnerability to opiates. We examined intravenous morphine self-administration after adolescent- vs. adult-onset, followed by extinction and cue-induced reinstatement.

Age- and sex-dependent amphetamine self-administration in rats.

Rationale: Recreational drug use peaks in the developmental stage of adolescence, and exposure to drugs during adolescence may predict drug dependence in adulthood. Nevertheless, adolescent drug vulnerability is not widely studied in animal models of drug intake, and very few studies have investigated sex differences in drug-related behavior during adolescence.

Objectives: We compared patterns of intravenous (i.

Routes to research for novice undergraduate neuroscientists.

Undergraduate students may be attracted to science and retained in science by engaging in laboratory research. Experience as an apprentice in a scientist's laboratory can be effective in this regard, but the pool of willing scientists is sometimes limited and sustained contact between students and faculty is sometimes minimal. We report outcomes from two different models of a summer neuroscience research program: an Apprenticeship Model (AM) in which individual students joined established research laboratories, and a Collaborative Learning Model (CLM) in which teams of students worked through a guided curriculum and then conducted independent experimentation.

Brains Rule!: a model program for developing professional stewardship among neuroscientists.

Brains Rule! Neuroscience Expositions, funded through a National Institute on Drug Abuse Science Education Drug Abuse Partnership Award, has developed a successful model for informal neuroscience education. Each Exposition is a "reverse science fair" in which neuroscientists present short neuroscience teaching modules to students. This study focuses on results of assessments conducted with neuroscientist presenters during Expositions at two sites, Atlanta, Georgia and Corpus Christi, Texas.

Behavioral and neurochemical responses to cocaine in periadolescent and adult rats.

Although recreational drug use by human adolescents is a well-known and long-standing problem, relatively little is known regarding differences in behavioral and physiological responses to abused substances in adolescent vs adult animals. The present study compared effects of the psychomotor stimulant, cocaine, in periadolescent (postnatal days 37-52) and adult (postnatal days 75-90) male Wistar rats. Locomotion and motor stereotypy were recorded after acute and repeated cocaine injections (0, 10, or 20 mg/kg cocaine, intraperitoneal (i.