Monthly Archives: May 2008
Turning off the genes for substance abuse.If psychiatric disorders, including depression and addiction, are rooted in nature, but modified by nurture, some better way of viewing the interaction between genes and the environment is desperately needed.Enter “epigenetics,” defined as the study of how gene expression can be modified without making direct changes to the DNA. Writing in Science News, Tina Hesman Saey explains that “epigenetic mechanisms alter how cells use genes but don’t change the DNA code in the genes themselves…. The ultimate effect is to finely tune to what degree a gene is turned on or off. Often the fine tuning is long-lasting, setting the level of a gene’s activity for the lifetime of the cell.”A common form of epigenetic modification involves adding molecules to the DNA structure. Adding molecules from a methyl group or an acetyl group can change the manner in which genes interact with a cell’s transcribing system. Cells can “mark” specific genes by attaching a methyl group consisting of three hydrogen atoms and one carbon atom to cytosine in the DNA base, effectively turning genes on or off without making major alterations to genetic structure. (Gene mutations or insertions, on the other hand, are capable of fundamentally altering the DNA protein structure.)Scientists have learned that epigenetic changes can be caused by environmental impacts, but the details are not well understood. We have not yet reached the point of being able to link a specific experience of stress or infection or chemical exposure to specific epigenetic alterations.What does any of this have to do with drug addiction or depression? One of the environmental impacts researchers have linked to epigenetic changes is drug addiction. The DNA double helix is packaged in proteins collectively called chromatin. One set of proteins, the histones, is a frequent site of epigenetic modification. In a study published in Neuron, Eric Nestler and co-workers in the Southwestern Medical Center at the University of Texas found that alterations in chromatin packaging were tied up with the dopamine release caused by cocaine addiction. The researchers concluded that chronic cocaine use was influenced by “chromatin remodeling.” Specifically, modulating histone activity “alters locomotor and rewarding responses to cocaine.”How does this work? As Saey writes in Science News: “Another gene, known as delta-FosB, also switches on when a wave of dopamine washes over the nucleus accumbens…. Delta-FosB teams up with other transcription factors and recruits enzymes that acetylate histones and remodel control regions of some genes….. Such findings suggest that medicines that interrupt or reverse epigenetic changes caused by drugs of abuse could one day prevent or cure addiction.”Image Credit: Science in School (Source: Addiction Inbox) Continue reading
The first large-scale analysis of proteins in the brains of monkeys addicted to cocaine reveals new information on how long-term cocaine use changes the amount and activity of various proteins affecting brain function. Continue reading
From The Harder They Fall”My father was an alcoholic, so I never really drank much. I kept away from it, but I didn’t realize that cocaine was really the same thing. Alcohol eventually started getting a little out of control, but in the form of ‘fine wine.’ That was my excuse….”So I didn’t consider wine a problem, but cocaine was a problem, and that got out of hand quite fast. It had a very bad effect on my marriage. The lies and deceit and everything that goes with addiction. I went from snorting it occasionally to now smoking it, doing freebase. Doing as much as I could. Finish a batch at four in the morning. Driving around the San Fernando Valley looking for some more of it. Driving while completely stoned, of course. How I was never in an accident, I just don’t know….”The using ended because I went down to the Betty Ford Center…. I didn’t thank God at the time time, however. I felt I’d lost a great friend or mistress, that I’d lost the one thing that I could totally trust–all that bullshit! It wasn’t until I started to work on myself at Betty Ford, which is a wonderful place as is any place that gets you sober….And, of course, it’s hard work, recovery. Less and less hard as the years have gone by, but you know, the way we live our lives is all recovery in one sense or another. We go through a shattering experience like that, and everything we do in life from then on is in a way influenced by what we’ve been through.”Excerpted from:The Harder They Fall, by Gary Stromberg and Jane Merrill. Center City, MN: Hazelden.Photo Credit: MTV News (Source: Addiction Inbox) Continue reading
Crack, free-base, and powderThe cocaine high is a marvel of biochemical efficiency. Cocaine works primarily by blocking the reuptake of dopamine molecules in the synaptic gap between nerve cells. Dopamine remains stalled in the gap, stimulating the receptors, resulting in higher dopamine concentrations and greater sensitivity to dopamine in general.Since dopamine is involved in moods and activities such as pleasure, alertness and movement, the primary results of using cocaine–euphoria, a sense of well being, physical alertness, and increased energy—are easily understood. Even a layperson can tell when lab rats have been on a cocaine binge. The rapid movements, sniffing, and sudden rearing at minor stimuli are not that much different in principle from the outward signs of cocaine intoxication among higher primates.Chemically, cocaine and amphetamine are very different compounds. Psychoactively, however, they are very much alike. Of all the addictive drugs, cocaine and speed have the most direct and most devastatingly euphoric effect on the dopamine systems of the brain. Writing in the November 2004 issue of Synapse, Jonathan D. Brodie and colleagues at the New York University School of Medicine reported that “A rapid elevation in nucleus accumbens dopamine characterizes the neurochemical response to cocaine, methamphetamine, and other drugs of abuse.”In the late 1990s, scientists at Johns Hopkins and NIDA had shown that opiate receptors play a role in cocaine addiction as well. PET scans demonstrated that cocaine addicts showed increased binding activity at mu opiate receptors sites in the brain during active cocaine addiction. Take away the cocaine, and the brain must cope with too many empty dopamine and endorphin receptors.Cocaine and amphetamine produce rapid classical conditioning in addicts, demonstrated by the intense cravings touched off by such stimuli as the sight of a building where the user used to buy or sell. Environmental impacts of this nature can produce marked blood flow increases to key limbic structures in abstinent addicts.When the crack “epidemic” first became news, it was clear that the old specialty of free-basing was now within reach of existing cocaine users. No paraphernalia needed except for a small pipe; no more butane and mixing; no muss, no fuss. Like basing, smoking crack was a drug dealer’s dream. The “rush” from smoking crack was more potent, but even more transient, than the short-lived high from nasal ingestionBoth the cocaine high and the amphetamine high are easily augmented with cigarettes or heroin. These combinations result in “nucleus accumbens dopamine overflow,” a state of neurochemical super saturation similar to the results obtained with the notorious “speedball”—heroin plus cocaine.It has been clear for more than a decade that most cocaine treatment programs are failures. In the case of the newly arrived crack cocaine, relapse rates after formal treatment sometimes approach one hundred per cent. Clearly, a piece of the puzzle has been missing. If receptors were the sites that controlled how drugs affected the mind, and if genes controlled how receptors were grown, then one implication of all the receptor theories was that sensitivity to addictive drugs could conceivably have a genetic basis. It was a large step in the right direction, because there were already good reasons for seeing alcoholism and other addictions as inherited dysfunctions in brain chemistry.–Excerpted from Addiction: The Search for a Cure © Dirk Hanson 2007Photo Credit: Legal Drug Alternatives (Source: Addiction Inbox) Continue reading
The purpose of the Drug-Free Workplace Kit is to provide public and private workplaces, from small to large and from local to global, with credible, authoritative, evidence-based information, resources, and tools for producing and maintaining drug-free workplace policies and programs. The Kit was assembled by the Division of Workplace Programs (DWP), in the Center for Substance Abuse Prevention, Substance Abuse And Mental Health Services Administration (SAMHSA), U.S. Department of Health and Human Services. DWP has unique and nationally important regulatory, knowledge development, and technical assistance roles and responsibilities for Federal and non-Federal workplaces, with respect to their drug-free workplace policies and programs.
Date Added: 05/15/08
Inventory #: SMA07-4230
This TIP, Substance Abuse Treatment and Domestic Violence, presents an introduction to the field of domestic violence. It give providers information on the role of substance abuse in domestic violence. Techniques for detecting and eliciting such information are supplied, along with ways to modify treatment to ensure victims’ safety and to stop the cycle of violence in both parties’ lives. Legal issues, including duty to warn and confidentiality, are discussed.
Date Added: 05/15/08
Inventory #: SMA08-4076
NSDUH: State Estimates of Persons Aged 18 or Older Driving Under the Influence Of Alcohol or Illicit Drugs
Combined data from 2004 to 2006 indicate that 15.1 percent of current drivers aged 18 or older drove under the influence of alcohol in the past 12 months (“past year”), and 4.7 percent drove under the influence of illicit drugs in the past year. Rates of past year driving under the influence of alcohol were highest among persons aged 18 or older in Wisconsin (26.4 percent), North Dakota (24.9 percent), Minnesota (23.5 percent), Nebraska (22.9 percent), and South Dakota (21.6 percent). Past year rates of driving under the influence of illicit drugs among persons aged 18 or older were highest in the District of Columbia (7.0 percent), Rhode Island (6.8 percent), Massachusetts (6.4 percent), Montana (6.3 percent), and Wyoming (6.2 percent).
Date Added: 05/15/08
Inventory #: NSDUH08-0417
Youth substance use in the past year was generally higher within one-parent households than within two-parent households for both mother-child and father-child pairs and were generally highest among youth in father-child pairs within one-parent households. Parent awareness of youth use of cigarettes and alcohol in the past year increased with the youth’s increasing age among both. Rates of parent awareness of youth substance use in the past year were generally higher among mothers in mother-child pairs than among fathers in father-child pairs and were generally highest among mothers in mother-child pairs within one-parent households.
Date Added: 05/15/08
Inventory #: NSDUH08-0424