Faculty Collaboration Database

Adrenal activity during repeated long-access cocaine self-administration is required for later CRF-Induced and CRF-dependent stressor-induced reinstatement in rats. Neuropsychopharmacology 2011 Jun;36(7):1444-54

Date

03/18/2011

Pubmed ID

21412222

Pubmed Central ID

PMC3096813

DOI

10.1038/npp.2011.28

Scopus ID

2-s2.0-79956020911 (requires institutional sign-in at Scopus site)   27 Citations

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 CRF(9-41) (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.

Author List

Graf EN, Hoks MA, Baumgardner J, Sierra J, Vranjkovic O, Bohr C, Baker DA, Mantsch JR

Author

John Mantsch PhD Chair, Professor in the Pharmacology and Toxicology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adrenalectomy
Analysis of Variance
Animals
Behavior, Animal
Cocaine
Conditioning, Operant
Corticosterone
Corticotropin-Releasing Hormone
Dopamine Uptake Inhibitors
Extinction, Psychological
Male
Peptide Fragments
Rats
Rats, Sprague-Dawley
Reinforcement Schedule
Self Administration