Effect of exercise and morphine on psychological and physical dependencies, BDNF and TrkB gene expression in rat's hippocampus.

OBJECTIVES: To compare the effect of exercise and morphine on abstinence syndrome and hippocampal gene expression in rat model. METHODS: Thirty adult male rats were exposed to voluntary wheel exercise (low, medium, high) for 28 days. The subjects entered Conditioned Place Preference (CPP) apparatus and experienced morphine (low, medium, high) CPP and followed by naloxone test. Correlation between exercise level, morphine injection, concurrent morphine administration and exercise with morphine CPP, BDNF and TrkB genes was determined. Rats were euthanized, decapitated and the hippocampus was removed. The expression of BDNF and TrkB genes were evaluated by real time PCR. RESULTS: Active rats ran an average of 839.18 m/d. A significant (P<0.001) correlation between exercise level, morphine injection, concurrent morphine administration and exercise with morphine CPP and BDNFand TrKB gene expressions was found. CONCLUSION: Voluntary exercise in different levels potentiates the brain rewarding system, CPP scale, and hippocampal BDNF and TrKB expressions. High range of voluntary exercise demonstrated an increase in the likelihood of developing addictive and drug-seeking behavior.

Epidemiologic Study of Opium Use in Pars Cohort Study: A Study of 9000 Adults in a Rural Southern Area of Iran.

BACKGROUND: Opium is one of the most common substances used worldwide with variable epidemiologic features in different regions. This study was performed in southern Iran, to find the epidemiology of opium use and its association with different factors and diseases. METHODS: This cross-sectional study was performed on baseline data extracted from Pars Cohort Study performed in Valashahr, a rural area in southern Iran. For any subject, information was collected about demographic factors, some common diseases including heart disease, stroke and hypertension and the state of using opium, other substances and cigarettes. RESULTS: There were 4276 males and 4988 females, with a mean age of 52.6 ± 9.7 years of whom 8.4% reported opium use (17.3% of males and 0.7% of females). In men, the history of stroke and heart disease were significantly more common in opium users (12.6% vs. 8.8%, P = 0.001 and 2.8% vs. 1.5%, P = 0.01, respectively) while the history of hypertension was significantly more common in non-opium users (7.8% vs. 10.3%, P = 0.04). Younger age, male gender, being non-married and positive history of joint pain, cigarette smoking and alcohol consumption were the factors associated with opium use. CONCLUSION: Opium use is common in non-married men who have a positive history of cigarette smoking and alcohol consumption in the rural population of southern Iran. It is associated with increased risk of heart disease and stroke and decreased risk of hypertension in males. Global interventional and preventive measures are required to control this complicated social problem.

Voluntary Wheel Running Induces Exercise-Seeking Behavior in Male Rats: A Behavioral Study.

BACKGROUND: Research evidence shows that exercise is associated with positive physical and mental health. Moreover, exercise and wheel running in rats activate overlapping neural systems and reward system. The most commonly used models for the study of rewarding and aversive effects of exercise involve using treadmill and wheel running paradigms in mice or rats. The purpose of our experiment was to study the influence of continuous voluntary exercise on exercise-seeking behavior. METHODS: In this experimental study, we used 24 adult male Sprague-Dawley rats weighing 275-300 g on average. Rats were divided into 3 experimental groups for 4 weeks of voluntary wheel running. Each rat ran in the cage equipped with a wheel during 24 hours. A within-subject repeated measure design was employed to evaluate the trend of running and running rates. RESULTS: We found that time and higher levels of exercise will increase exercise tendency. Our results also show that the interaction of exercise within 4 weeks and different levels of exercise can significantly promote rats' exercise-seeking behavior (F = 5.440; df = 2.08; P < 0.001). CONCLUSION: Our data suggest that voluntary wheel running can increase the likelihood of extreme and obsessive exercising which is a form of non-drug addiction.

Effects of Dexamphetamine and Music on Reversal Learning.

BACKGROUND: Reversal learning has proven to be a valuable task in assessing the inhibitory process that is central to executive control. Psycho-stimulants and music are prevalent factors that influence cognition. OBJECTIVES: The present study aimed at investigating the influences of dexamphetamine and music on inhibitory control. MATERIALS AND METHODS: This experimental study was conducted between May and June 2014 in the laboratory animal center of Shiraz University of Medical Sciences, Shiraz, Iran. Thirty mice were divided to five groups including a control group, a witness group, and three experimental groups. Food availability was restricted in order to maintain the subjects at 85% of their free-feeding body weight for behavioral testing. After discrimination learning, animals received four injections of 2 mg/kg dexamphetamine at two-hour intervals. The music group was exposed to music half an hour before reversal learning. RESULTS: According to the results of the repeated measure analysis of variance (ANOVA), music increased errors (mean difference: -2.40, 95% CI: -3.59 to -1.22), yet dexamphetamine had no significant effect on reversal learning. Due to various advantages, we transited to the mixed model that showed increasing (Beta: 2.2 95% CI: 0.26 to 4.13) and borderline (Beta: 1.8 95% CI: -0.13 to 3.73) effects on the number of errors for dexamphetamine and music group, respectively. CONCLUSIONS: Drug-treated subjects were impaired in their ability to modulate behavior, based upon changing information about stimulus-reward associations, possibly due to the inability to inhibit their response. These effects may have relevance to some mental disorders such as drug-abuse, schizophrenia, and obsessive-compulsive disorder.

Prevalence of HIV, HCV, and High-Risk Behaviors for Substance Users in Drop in Centers in Southern Iran.

OBJECTIVES: Drop In Centers (DICs) are organizations in which health and social services are delivered to drug users on the basis of harm-reduction strategies. The aim of this epidemiological study was to estimate the prevalence of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infection at these centers over a 6-year period. METHODS: All of the DICs (7 in total) visited were located in Shiraz, the capital city of Fars province, southern Iran. Every patient record in these centers was studied between April 2006 and April 2011. Complementary information on the frequency of HIV was collected from the Voluntary Counseling and Testing services. A logistic regression model was applied to data analysis. The study explored risk factors associated with HIV and HCV infections, which were primarily high-risk sexual behavior. RESULTS: This study examined 1,327 people, 79.5% of whom were males. The mean age of first substance use and the first injection among intravenous drug users (IDUs) were 20.24 ± 6.11 and 26.5 ± 7.3 years, respectively. In total, 13.5% and 20.2% of the subjects who registered at the DICs were infected with HCV and HIV, respectively. Shared injection, history of imprisonment, maleness, unsafe sex, inadequate housing, and low education were risk factors for HIV infection. Shared injection, unsafe sex, history of imprisonment, and maleness were predisposing factors for HCV infection. A history of imprisonment and substance use upon registration at the DIC were significant risk factors for female sex workers. CONCLUSIONS: Our study emphasized the implementation of preventive measures like education and needle exchange program as harm-reduction strategies. Drop in Centers are important for the management of health problems, including HIV infection and social problems such as crime. Periodic epidemiological studies on DICs are necessary to monitor and modulate the services delivered by these centers.

Opioids use in male population referred for mandatory urine opioid screen before marriage in shiraz-iran.

OBJECTIVE: To assess the prevalence of opioid abuse in a sample of male population in Shiraz, Iran. METHODS: A representative sample of 1219 subjects (aged 16 years or older) who were referred for urine opioid screen (UOS) as a mandatory test before marriage in Shiraz in 2005 were enrolled in this study. RESULTS: Mean age of the participants was 26.17 years (SD=6.12), ranging from 16 to 75 years. From them, 121 participants (9.93%) had positive urine opioid test. They were retested at least few days later by thin layer chromatography (TLC). The results showed that 22 (1.80%) had positive urine opioid test (based on TLC), whose mean age was 25.7 years, ranging from 19 to 32 years. CONCLUSION: It can be concluded that at least 1.80% of men referred for UOS as a mandatory test before marriage used opioids. These results should be considered when preventive and therapeutic programs are being planned.