Abstract
Background: Alcohol use in adolescence may increase susceptibility to substance use disorders (SUDs) in adulthood. This study determined if voluntary ethanol (EtOH) consumption during adolescence, combined with social isolation, alters the trajectory of EtOH and nicotine intake during adulthood, as well as activating brain neuroinflammation.
Methods: Adolescent male isolate- and group-housed rats were given 0.2 % saccharin/20 % EtOH (Sacc/EtOH) or water using intermittent 2-bottle choice; controls were given water in both bottles (n=17–20 per group). Some rats from each group (n=5–6) were euthanized one week later to measure autoradiographic [3H]PK-11195 binding, an indicator of microglial reactivity, and the remainder (n=11–14 per group) were tested in adulthood in 2-bottle choice, followed by nicotine self-administration using an incremental fixed ratio (FR) schedule with Sacc/EtOH and water concurrently available.
Results: Isolation housing increased adolescent intake of Sacc/EtOH, but the increase did not produce an observable neuroimmunological response in brain. Adolescent EtOH exposure decreased adult intake of both Sacc/EtOH and unsweetened EtOH, with isolate-housed rats showing a greater effect than group-housed rats. In the co-use model, a cross-price economic demand analysis revealed a substitutional relationship between Sacc/ EtOH and nicotine, but no effect of adolescent Sacc/EtOH exposure. Compared to group-housed rats, isolate-housed rats were more sensitive to the changing price of nicotine and showed greater substitutability of Sacc/ EtOH for nicotine.
Conclusion: The current results suggest that adolescent EtOH exposure per se, with or without isolation stress, does not likely explain the enhanced risk for either alcohol or nicotine use later in life.
Document Type
Article
Publication Date
2024
Digital Object Identifier (DOI)
https://doi.org/10.1016/j.dadr.2024.100277
Funding Information
This work was supported by the National Institutes of Health [grant numbers R01 AA025591; T32 DA035200].
Repository Citation
Shaykin, Jakob D.; Olyha, Lidia N.; Van Doorn, Catherine E.; Hales, Joshua D.; Chandler, Cassie M.; Hopkins, Deann M.; Nixon, Kimberly; Beckmann, Joshua S.; Pauly, James R.; and Bardo, Michael T., "Effects of isolation stress and voluntary ethanol exposure during adolescence on ethanol and nicotine co-use in adulthood using male rats" (2024). Psychology Faculty Publications. 224.
https://uknowledge.uky.edu/psychology_facpub/224
Notes/Citation Information
2772-7246/© 2024 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).