Next Article in Journal
Characteristic of Stimulus Frequency Otoacoustic Emissions: Detection Rate, Musical Training Influence, and Gain Function
Next Article in Special Issue
Association of Polygenic Liability for Alcohol Dependence and EEG Connectivity in Adolescence and Young Adulthood
Previous Article in Journal
Serum Levels of Tumor Necrosis Factor-α and Loudness Dependence of Auditory Evoked Potentials at Pretreatment and Posttreatment in Patients with Major Depressive Disorder
Previous Article in Special Issue
C57BL/6 Substrain Differences in Pharmacological Effects after Acute and Repeated Nicotine Administration
Open AccessArticle

Endocannabinoids and Fear-Related Behavior in Mice Selectively Bred for High or Low Alcohol Preference

1
Department of Psychological Sciences, Purdue University, West Lafayette, IN 47907, USA
2
Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA
*
Author to whom correspondence should be addressed.
Brain Sci. 2019, 9(10), 254; https://doi.org/10.3390/brainsci9100254
Received: 16 July 2019 / Revised: 19 September 2019 / Accepted: 24 September 2019 / Published: 26 September 2019
Alcohol use disorders (AUDs) have a high incidence of co-morbidity with stress-related psychopathologies, such as post-traumatic stress disorder (PTSD). Genetic and pharmacological studies support a prominent role for the endocannabinoid system (ECS) in modulating stress-related behaviors relevant to AUDs and PTSD. Mouse lines selectively bred for high (HAP) and low (LAP) alcohol preference show reproducible differences in fear-potentiated startle (FPS), a model for PTSD-related behavior. The first experiment in this study assessed levels of the endocannabinoids, anandamide (AEA) and sn-2 arachidonylglycerol (2-AG), in the prefrontal cortex (PFC), amygdala (AMG), and hippocampus (HIP) of male and female HAP1 and LAP1 mice following the expression of FPS to determine whether ECS responses to conditioned-fear stress (FPS) were correlated with genetic propensity toward high or low alcohol preference. The second experiment examined effects of a cannabinoid receptor type 1 agonist (CP55940) and antagonist (rimonabant) on the expression of FPS in HAP1 and LAP1 male and female mice. The estrous cycle of females was monitored throughout the experiments to determine if the expression of FPS differed by stage of the cycle. FPS was greater in male and female HAP1 than LAP1 mice, as previously reported. In both experiments, LAP1 females in diestrus displayed greater FPS than LAP1 females in metestrus and estrus. In the AMG and HIP, AEA levels were greater in male fear-conditioned HAP1 mice than LAP1 mice. There were no line or sex differences in effects of CP55940 or rimonabant on the expression of FPS. However, surprisingly, evidence for anxiogenic effects of prior treatment with CP55940 were seen in all mice during the third drug-free FPS test. These findings suggest that genetic differences in ECS function in response to fear-conditioning stress may underlie differences in FPS expression in HAP1 and LAP1 selected lines. View Full-Text
Keywords: alcohol preference; amygdala; anandamide; estrous; endocannabinoid; fear; hippocampus; mice; prefrontal cortex; post-traumatic stress disorder alcohol preference; amygdala; anandamide; estrous; endocannabinoid; fear; hippocampus; mice; prefrontal cortex; post-traumatic stress disorder
Show Figures

Figure 1

MDPI and ACS Style

Kirchhoff, A.M.; Barker, E.L.; Chester, J.A. Endocannabinoids and Fear-Related Behavior in Mice Selectively Bred for High or Low Alcohol Preference. Brain Sci. 2019, 9, 254.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop