Exercise increases leptin levels correlated with IGF-1 in hippocampus and prefrontal cortex of adolescent male and female rats

AbstractBackgroundDrinking alcohol is facilitated by social interactions with peers, especially during adolescence. The importance of peer social influences during adolescence on alcohol and substance use have recently received more attention. We have shown that social interaction with an alcohol-intoxicated peer influences adolescent alcohol drinking differently in male and female rats using the demonstrator-observer paradigm. The present set of experiments analyzed the social interaction session to determine behaviors that influence alcohol drinking in adolescent male and female rats.MethodsSpecifically, in experiment one we determined which behaviors were altered during social interaction with an alcohol-intoxicated demonstrator and assessed changes in ethanol intake in adolescent observers. Experiment two examined changes in voluntary saccharin consumption to determine if social interaction with an alcohol-intoxicated demonstrator altered consumption of a palatable solution. In experiment three, we administered a low (5 mg/kg) or high (20 mg/kg) dose of cocaine to the demonstrator and assessed changes in the adolescent observers to determine if social interaction with a ‘drugged’ peer altered social behaviors and voluntary ethanol intake.ResultsWe showed that social interaction with an alcohol-intoxicated demonstrator (1) decreased social play and increased social investigation and social contact in adolescent male and female observers, (2) did not alter non-social behaviors, (3) did not alter saccharin consumption and (4) increased voluntary ethanol intake in adolescent female but not male observers. When the peer was injected with cocaine (1) social play was dose-dependently decreased, (2) there were no changes in other social or non-social behaviors, and (3) voluntary ethanol intake in adolescent male and female observers was unaffected.ConclusionsThe present results are consistent and extend our previous work showing that social interaction with an alcohol-intoxicated peer selectively alters social behaviors and alcohol-drinking in adolescent rats. Females appear to be more sensitive to elevating effects of social interaction on voluntary ethanol consumption.

Download Full-text

Perinatal exposure to diesel exhaust origin secondary organic aerosol induces autism-like behavior in rats

10.21203/rs.3.rs-41390/v3 ◽

2020 ◽

Author(s):

Tin Tin Win Shwe ◽

Chaw Kyi Tha Thu ◽

Yuji Fujitani ◽

Shinji Tsukahara ◽

Seishiro Hirano

Keyword(s):

Prefrontal Cortex ◽

Diesel Exhaust ◽

Secondary Organic Aerosol ◽

Organic Aerosol ◽

Female Rats ◽

Perinatal Exposure ◽

Male And Female ◽

Glutamate Concentration ◽

Immunological Markers ◽

Male And Female Rats

Abstract Background: Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired social communication, poor social interactions and repetitive behaviors. The exact cause and mechanism of autism remains unknown. Both genetic and environmental factors may involve in ASD. In this study, we used diesel exhaust (DE) origin secondary organic aerosol (DE-SOA) as environmental pollutants. DE-SOA was generated by oxidative reaction of mixing DE with ozone. The aim of present study is to examine autism-like behaviors and related gene expressions in rats exposed to DE-SOA perinatally. Sprague-Dawley pregnant rats were exposed to clean air (control), DE and DE-SOA in the exposure chamber for 5 h per day (from 10:00 pm to 3:00 am), 5 days a week excluding weekends from gestational day 14 to postnatal day 21 with their pups. At postnatal day 21, the male and female offspring rats were allocated into three different groups as follows: 1) rats exposed to clean filtered air; 2) rats exposed to DE; 3) rats exposed to DE-SOA. Social behaviors were investigated at 10~13-weeks-old rats using a 3-chambered social behavior test, social dominance tube test and marble burying test. Prefrontal cortex was collected to examine neurological and immunological markers, and glutamate concentration, using real-time RT-PCR and ELISA methods. Results: DE-SOA-exposed male and female rats showed poor sociability and social novelty preference, socially dominant behavior and increased repetitive behavior compared with the control rats. The mRNA expression levels of serotonin receptor (5-HT(5B)) and brain-derived neurotrophic factor (BDNF) were down-regulated whereas interleukin 1 b　(IL-b), and heme oxygenase 1 (HO-1) were upregulated in the prefrontal cortex of male and female rats exposed to DE-SOA compared to the control rats. Glutamate concentration was increased significantly in the prefrontal cortex of both male and female rats exposed to DE-SOA.Conclusion: Our results indicate that perinatal exposure to DE-SOA may induce autism-like behavior in rats by modulating neurological and immunological markers in the prefrontal cortex.

Download Full-text