Adrenal Activity during Repeated Long-Access Cocaine Self-Administration is Required for Later CRF-Induced and CRF-Dependent Stressor-Induced Reinstatement in Rats

Authors

Evan N. Graf, Marquette UniversityFollow
Michael A. Hoks, Marquette University
Jean Baumgardner, Marquette University
Jose Sierra, Marquette University
Oliver Vranjkovic, Marquette UniversityFollow
Colin Bohr, Marquette University
David A. Baker, Marquette UniversityFollow
John R. Mantsch, Marquette UniversityFollow

Document Type

Article

Language

eng

Format of Original

11 p.

Publication Date

3-2011

Publisher

Nature Publishing Group (Macmillan Publishers Limited)

Source Publication

Neuropsychopharmacology

Source ISSN

0893-133X

Original Item ID

doi: 10.1038/npp.2011.28

Abstract

Understanding the neurobiological processes that contribute to the establishment and expression of stress-induced regulation of cocaine use in addicted individuals is important for the development of new and better treatment approaches. It has been previously shown that rats self-administering cocaine under long-access conditions (6 h daily) display heightened susceptibility to the reinstatement of extinguished cocaine seeking by a stressor, electric footshock, or i.c.v. administration of the stressor-responsive neuropeptide, corticotropin-releasing factor (CRF). This study tested the hypothesis that adrenal responsiveness during earlier long-access cocaine self-administration (SA) is necessary for the establishment of later CRF-dependent stress-induced reinstatement. Reinstatement by footshock, but not a cocaine challenge (10 mg/kg, i.p.) following long-access SA, was blocked by i.c.v. administration of the CRF receptor antagonist, α-helical CRF₉₋₄₁ (10 μg). Elimination of SA-induced adrenal responses through surgical adrenalectomy and diurnal corticosterone replacement (ADX/C) before 14 days of SA under long-access conditions had minimal impact on cocaine SA, but blocked later footshock-induced reinstatement. By contrast, ADX/C after SA, but before extinction and reinstatement testing, failed to reduce footshock-induced reinstatement. Likewise, ADX/C before 14 days long-access SA prevented later reinstatement by i.c.v. CRF (0.5 or 1.0 μg). However, significant CRF-induced reinstatement was observed when rats underwent ADX/C following SA, but before extinction and reinstatement testing, although a modest but statistically nonsignificant reduction in sensitivity to CRF's reinstating effects was observed. Taken together, these findings suggest that adrenal-dependent neuroadaptations in CRF responsiveness underlie the increased susceptibility to stress-induced relapse that emerges with repeated cocaine use.

Comments

Accepted version. Neuropsychopharmacology, Vol. 36 (June, 2011): 1444-1454. DOI. © 2011 Nature Publishing Group. Used with permission.

Recommended Citation

Graf, Evan N.; Hoks, Michael A.; Baumgardner, Jean; Sierra, Jose; Vranjkovic, Oliver; Bohr, Colin; Baker, David A.; and Mantsch, John R., "Adrenal Activity during Repeated Long-Access Cocaine Self-Administration is Required for Later CRF-Induced and CRF-Dependent Stressor-Induced Reinstatement in Rats" (2011). Biomedical Sciences Faculty Research and Publications. 27.
https://epublications.marquette.edu/biomedsci_fac/27