Conor Murray

University of California, Los Angeles | UCLA · Department of Psychiatry and Biobehavioural Sciences

Protein translation is essential for some forms of synaptic plasticity. Here we used fluorescent noncanonical amino acid tagging (FUNCAT) to examine whether dopamine modulates protein translation in cultured nucleus accumbens (NAc) medium spiny neurons (MSN). These neurons were co-cultured with cortical neurons to restore excitatory synapses. We me...

Neural complexity correlates with one's level of consciousness. During coma, anesthesia, and sleep, complexity is reduced. During altered states, including after lysergic acid diethylamide (LSD), complexity is increased. In the present analysis, we examined whether low doses of LSD (13 and 26 µg) were sufficient to increase neural complexity in the...

Protein translation is essential for some forms of synaptic plasticity. We used nucleus accumbens (NAc) medium spiny neurons (MSN), co-cultured with cortical neurons to restore excitatory synapses, to examine whether dopamine modulates protein translation in NAc MSN. FUNCAT was used to measure translation in MSNs under basal conditions and after di...

Relapse is a major problem in treating methamphetamine use disorder. “Incubation of craving” during abstinence is a rat model for persistence of vulnerability to craving and relapse. While methamphetamine incubation has previously been demonstrated in male and female rats, it has not been demonstrated after withdrawal periods greater than 51 d and...

Renewed interest in classic psychedelics as treatments for psychiatric disorders warrants a deeper understanding of their neural mechanisms. Single, high doses of psychedelic drugs have shown promise in treating depressive disorders, perhaps by reversing deficits in reward processing in the brain. In addition, there are anecdotal reports that repea...

Rationale Greater availability of cannabis in the USA has raised concerns about adverse effects of the drug, including possible amotivational states. Lack of motivation may be assessed by examining acute effects of cannabinoids on reward processing. Objectives This study examined single doses of delta-9-tetrahydrocannabinol (∆9-THC; 7.5, 15 mg ora...

Rationale Classical psychedelics, including psilocybin and lysergic acid diethylamide (LSD), are under investigation as potential therapeutic agents in psychiatry. Whereas most studies utilize relatively high doses, there are also reports of beneficial effects of “microdosing,” or repeated use of very low doses of these drugs. The behavioral and ne...

Increased cannabis availability has contributed to increased use with concomitant incidence of adverse effects. One risk factor for adverse drug reactions may be age. There is preclinical evidence that acute effects of delta-9-tetrahydrocannabinol (THC), the primary active constituent of cannabis, are greater during adolescence, but this has not be...

Relapse is a major challenge to the treatment of substance use disorders. A progressive increase in cue-induced drug craving, termed incubation of craving, is observed after withdrawal from multiple drugs of abuse in humans and rodents. Incubation of cocaine craving involves the strengthening of excitatory synapses onto nucleus accumbens (NAc) medi...

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 subje...

Many studies have demonstrated that negative allosteric modulators (NAM) of metabotropic glutamate receptor 5 (mGlu5) reduce cocaine and methamphetamine seeking in extinction-reinstatement animal models of addiction. Less is known about effects of mGlu5 NAMs in abstinence models, particularly for methamphetamine. We used the incubation of drug crav...

Alcohol abuse and dependence remain significant public health issues, and yet the brain circuits that are involved in the rewarding effects of alcohol are poorly understood. One promising way to study the effects of alcohol on neural activity is to examine its effects on functional connectivity between brain areas involved in reward and other funct...

Introduction Alcohol is among the most commonly used psychoactive drugs, yet it can produce markedly different subjective effects in different people. Certain effects, including both heightened stimulatory effects and lesser sedative effects, are thought to predict repeated or excessive use. However, we do not fully understand the nature of these i...

Background Controlled drug challenge studies provide valuable information about the acute behavioral effects of drugs, including individual differences that may affect risk for abuse. One question that arises in such studies is whether a single administration of a drug (and placebo) provides an accurate measure of response to the drug. Methods Her...

Cue-induced drug craving progressively intensifies after withdrawal from self-administration of cocaine, methamphetamine, and other drugs of abuse, a phenomenon termed incubation of craving. For cocaine and methamphetamine, expression of incubated craving ultimately depends on strengthening of nucleus accumbens (NAc) synapses through an accumulatio...

In Huntington's disease (HD), corticostriatal and striatopallidal projection neurons preferentially degenerate as a result of mutant huntingtin expression. Pathological deficits in nitric oxide (NO) signaling have also been reported in corticostriatal circuits in HD, however, the impact of age and sex on nitrergic transmission is not well character...

AMPA receptor (AMPAR) transmission onto medium spiny neurons (MSNs) of the adult rat nucleus accumbens (NAc) is normally dominated by GluA2-containing, Ca²⁺-impermeable AMPAR (CI-AMPARs). However, GluA2-lacking, Ca²⁺-permeable AMPA receptors (CP-AMPARs) accumulate after prolonged withdrawal from extended-access cocaine self-administration and, ther...

Background: The incubation of cue-induced drug craving in rodents provides a model of persistent vulnerability to craving and relapse in human addicts. After prolonged withdrawal, incubated cocaine craving depends on strengthening of nucleus accumbens (NAc) core synapses through incorporation of Ca(2+)-permeable alpha-amino-3-hydroxy-5-methyl-4-is...

The endocannabinoids are lipid-derived signaling molecules that control feeding and energy balance by activating CB1-type cannabinoid receptors in brain and peripheral tissues. Previous studies have shown that oral exposure to dietary fat stimulates endocannabinoid signaling in the rat small intestine, which provides positive feedback that drives f...