Ian A Mendez

Ian A Mendez
University of Texas at El Paso | UTEP · School of Pharmacy

Ph.D.

About

35
Publications
3,022
Reads
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976
Citations
Introduction
I have over 15 year of experience working in Cellular and Behavioral Neuroscience. By utilizing experimental methods in biology, pharmacology, behavior, genetics, and neurochemistry, I investigate phenomena such as reward seeking and taking behaviors, impaired economic cost-benefit decision making, and how metabolic mechanisms promote feeding disorders and obesity. These processes are relevant to a myriad of psychiatric disorders, with particularly strong implications for addiction.
Additional affiliations
September 2017 - present
University of Texas at El Paso
Position
  • Professor
January 2012 - August 2017
University of California, Los Angeles
Position
  • PostDoc Position
September 2011 - November 2011
California State University, San Marcos
Position
  • Consultant

Publications

Publications (35)
Article
The goal of our laboratory is to study the mechanisms that promote nicotine use, particularly in vulnerable populations. To more closely mimic human use patterns, the present study employed nicotine vapor methods involving passive exposure for 14 days in adolescent and adult female and male rats. Age and sex differences in approach behavior (nosepo...
Article
Full-text available
While the cognitive enhancing effects of nicotine use have been well documented, it has also been shown to impair decision making. The goal of this study was to determine if exposure to nicotine vapor increases risky decision making. The study also aims to investigate possible long-term effects of nicotine vapor exposure on the expression of genes...
Preprint
Full-text available
In recent years, there has been a dramatic increase in nicotine vapor consumption via electronic nicotine delivery systems (i.e., e-cigarettes), particularly in adolescents. While recent work has focused on the health effects of nicotine vapor exposure, its effects on the brain and behavior remain unclear. In this study, we assessed the effects tha...
Article
Introduction: Traditional cigarette use influences cost-benefit decision making by promoting impulsive choice. However, the impact of exposure via electronic nicotine delivery systems on impulsive choice remains unclear. Hence, the present study examined the short- and long-term effects of nicotine vapor on impulsive choice. Methods: Twenty-four...
Article
Prior work in male rodents established that the medial habenula‐interpeduncular nucleus (MHb‐IPN) pathway modulates nicotine withdrawal. Specifically, withdrawal severity has been closely associated with inhibitory tone in the IPN via interneurons that release γ‐aminobutyric acid (GABA). Inhibitory tone in the IPN is regulated by projections from t...
Article
Background and purpose Innovative delivery of research education and training in pharmacy education improves student perception of, and involvement in, professional pharmacy research. The purpose of this project was to utilize a flipped-classroom video technology approach to introduce our Capstone research experience and to assess the impact of the...
Article
The present study assessed sex differences and the role of ovarian hormones in nicotine withdrawal. Study 1 compared physical signs, anxiety-like behavior, and corticosterone levels in male, intact female, and ovariectomized (OVX) female rats during nicotine withdrawal. Estradiol (E2) and progesterone levels were also assessed in intact females tha...
Preprint
Full-text available
The present study assessed sex differences and the role of ovarian hormones in the behavioral effects of nicotine withdrawal. Study 1 compared physical signs, anxiety-like behavior, and corticosterone levels in male, intact female, and ovariectomized (OVX) female rats during nicotine withdrawal. Estradiol (E2) and progesterone levels were also asse...
Preprint
Full-text available
Background Previous studies have shown that exposure to nicotine smoke increases impulsivity. Surprisingly, research investigating the effects of electronic cigarette nicotine vapor exposure on impulsivity has not been conducted. Therefore, the present study examined the effects of nicotine vapor exposure on impulsive choice. Methods Twenty-four a...
Article
Full-text available
The two highly homologous non-visual arrestins, beta-arrestin 1 and 2, are ubiquitously expressed in the central nervous system, yet knowledge of their disparate roles is limited. While beta-arrestin 2 (βarr2) has been implicated in several aspects of reward-related learning and behavior, very little is known about the behavioral function of beta-a...
Data
The number of mice removed from each stage of the cocaine IVSA experiment. (DOCX)
Data
Individual datapoints for the cocaine IVSA experiment shown in Fig 1. The number of cocaine infusions earned by KO and WT mice during the A) first 5 days of FR1 and during B) the last 3 days of FR1, FR2 and FR5. The number of within-session active lever presses during C) the fifth day of FR1, D) the first day of FR2 and E) the first day of FR5 in 3...
Data
Survival plot of mice reaching acquisition criteria at FR1 of cocaine IVSA. WT mice (n = 22) reached acquisition criteria faster than the KO mice (n = 19) during the FR1 stage of cocaine self-administration experiments (p < 0.05). (TIF)
Data
Individual datapoints for the food-reinforced Pavlovian and instrumental training experiment shown in Fig 2. A) Magazine entries per minute during Pavlovian training. B) Lever presses per minute during instrumental training sessions. C) Daily lever presses per minute averaged across the three random ratio schedules. D) Lever pressing rate during th...
Data
Individual datapoints for the IV curve in WT and KO neurons. (TIF)
Data
Individual datapoints for the chronic inhibition of GluN2B-NMDAR experiment shown in Fig 6. A) Lever presses per minute during instrumental training. B) Magazine entry rate during instrumental training sessions. (TIF)
Article
Full-text available
Smoking to control body weight is an obstacle to smoking cessation, particularly in western cultures where diets are often rich in calories derived from fat sources. The purpose of this study was to investigate the effects of continuous nicotine administration on meal patterns in rats fed a high-fat diet. Male rats were housed in cages designed to...
Article
Full-text available
Opioid peptides are implicated in processes related to reward and aversion; however, how specific opioid peptides are involved remains unclear. We investigated the role of nociceptin (NOC) in voluntary licking for palatable and aversive tastants by studying the effect of intracerebroventricularly administered NOC on licking microstructure in wild-t...
Article
Full-text available
Studies implicate opioid transmission in hedonic and metabolic control of feeding, though roles for specific endogenous opioid peptides have barely been addressed. Here, we studied palatable liquid consumption in pro-enkephalin knockout (PENK KO) and β-endorphin-deficient (BEND KO) mice, and how the body weight of these mice changed during consumpt...
Article
Nicotinic receptors have been linked to a wide range of cognitive and behavioral functions, but surprisingly little is known about their involvement in cost benefit decision making. The goal of these experiments was to determine how nicotinic acetylcholine receptor (nAChR) expression is related to two forms of cost benefit decision making. Male Lon...
Article
Full-text available
Rationale Alterations in cost–benefit decision making accompany numerous neuropsychiatric conditions, including schizophrenia, attention deficit hyperactivity disorder, and addiction. Central cholinergic systems have been linked to the etiology and/or treatment of many of these conditions, but little is known about the role of cholinergic signaling...
Article
The LPHN3 gene has been associated with both attention deficit-hyperactivity disorder (ADHD) and addiction, suggesting that it may play a role in the etiology of these disorders. Unfortunately, almost nothing is known about the normal functions of this gene, which has hampered understanding of its potential pathogenic role. To begin to characterize...
Article
Full-text available
Many psychiatric disorders are characterized by abnormal risky decision-making and dysregulated dopamine receptor expression. The current study was designed to determine how different dopamine receptor subtypes modulate risk-taking in young adult rats, using a "Risky Decision-making Task" that involves choices between small "safe" rewards and large...
Article
Exposure to tobacco smoke during pregnancy is associated with a range of adverse outcomes in offspring, including cognitive deficits and increased incidence of attention deficit-hyperactivity disorder, but there is a considerable controversy with regard to the causal role of tobacco smoke in these outcomes. To determine whether developmental exposu...
Article
Full-text available
Cocaine use is associated with high levels of impulsive choice (preference for immediate over delayed rewards), but it is not clear whether cocaine use causes elevated impulsive choice, or whether elevated impulsive choice is solely a predisposing factor for cocaine use. This study examined the effects of prior cocaine self-administration on rats p...
Article
The ability to make advantageous choices among outcomes that differ in magnitude, probability, and delay until their arrival is critical for optimal survival and well-being across the lifespan. Aged individuals are often characterized as less impulsive in their choices than their young adult counterparts, demonstrating an increased ability to forgo...
Article
Drug-addicted individuals show high levels of impulsive choice, characterized by preference for small immediate over larger but delayed rewards. Although the causal relationship between chronic drug use and elevated impulsive choice in humans has been unclear, a small but growing body of literature over the past decade has shown that chronic drug a...
Article
Exposure to psychostimulant drugs of abuse such as amphetamine can result in long-lasting "sensitization" of reward-directed behavior, such that subjects display enhancements in behavior directed by and toward rewards and reward-predictive cues (i.e. "incentive sensitization"). The purpose of these experiments was to determine the degree to which s...
Article
Full-text available
Pavlovian conditioning with a discrete reward-predictive visual cue can elicit two classes of behaviors: "sign-tracking" (approach toward and contact with the cue) and "goal-tracking" (approach toward the site of reward delivery). Sign-tracking has been proposed to be linked to behavioral disorders involving compulsive reward-seeking, such as addic...
Article
Full-text available
N-Methyl-D: -aspartate (NMDA) receptors have an important role in different forms of behavioral and neural plasticity. Evidence suggests that these receptors may also be involved in plasticity arising from long-term treatment with different drugs of abuse, including tolerance, sensitization, and physical dependence. There is abundant evidence demon...
Article
Cocaine addiction is associated with long-term cognitive alterations including deficits on tests of declarative/spatial learning and memory. To determine the extent to which cocaine exposure plays a causative role in these deficits, adult male Long-Evans rats were given daily injections of cocaine (30 mg/kg/day x 14 days) or saline vehicle. Three m...
Article
Full-text available
In this study, the authors examined the long-term effects of prior exposure to cocaine on a delay-discounting task commonly used to measure impulsive choice. Male Long-Evans rats received daily intraperitoneal injections of 30 mg/kg cocaine HCl or saline for 14 days. Following 3 weeks of withdrawal, rats began training. On each trial, rats were giv...
Article
Full-text available
Learning models of associative and nonassociative drug tolerance predict that the development of contextual tolerance to drug effects is disrupted when the drug is delivered at short interdose intervals (IDIs). The authors examined the impact of 1 long IDI and 2 short IDIs in the development of contextual nicotine tolerance. Associative tolerance w...

Projects

Projects (3)
Project
Identify the role of nociceptin/orphanin FQ in reward and motivational processes and if intervening in this role impacts addiction-related processes.
Project
Projects aims to unravel the role of opioids in determining ongoing and stimulated changes in affective states, particularly those pertinent to addiction. Interactions with other neurosignaling molecules such as dopamine are of particular interest.