title: Repeated stress alters the ability of nicotine to activate the hypothalamic-pituitary-adrenal axis.
abstract: Acute nicotine administration has been shown to activate the hypothalamic-pituitary-adrenal (HPA) axis and stimulate secretion of adrenocorticotrophic hormone (ACTH), corticosterone/cortisol and beta-endorphin (beta-END) in both rodents and humans, raising the possibility that activation of the HPA axis by nicotine may mediate some of the effects of nicotine. Since stress can increase the risk of drug use and abuse, we hypothesized that repeated stress would increase the ability of nicotine to stimulate the secretion of HPA hormones. To test our hypothesis, mice were exposed to repeated stress (swimming in 15 degrees C water for 3 min/day for 5 days) and killed 15 min after injection of saline or nicotine (0.1 mg/kg, s.c.). Repeated exposure to stress increased the ability of nicotine to stimulate plasma ACTH (p<0.05) and beta-END (p<0.05), but not corticosterone secretion. In contrast, repeated exposure to stress increased the post-saline injection levels of corticosterone (p<0.05), but not ACTH and beta-END. The present results suggest that chronic stress leads to an enhanced sensitivity of some components of the HPA axis to a subsequent nicotine challenge.
authors.affiliation: Division of Endocrinology, Molecular Medicine and Metabolism, Department of Medicine, Charles R. Drew University of Medicine & Sciences-David Geffen School of Medicine at UCLA, Los Angeles, California 90059, USA.
authors.forename: Kabirullah
authors.initials: K
authors.lastname: Lutfy
authors.forename: Maria C
authors.initials: MC
authors.lastname: Brown
authors.forename: Namiko
authors.initials: N
authors.lastname: Nerio
authors.forename: Otaren
authors.initials: O
authors.lastname: Aimiuwu
authors.forename: Benjamin
authors.initials: B
authors.lastname: Tran
authors.forename: Adrian
authors.initials: A
authors.lastname: Anghel
authors.forename: Theodore C
authors.initials: TC
authors.lastname: Friedman
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000097:blood / Q000378:metabolism; D000818:Animals; D002908:Chronic Disease; D003345:Corticosterone / Q000097:blood / Q000378:metabolism; D004195:Disease Models, Animal; D007030:Hypothalamo-Hypophyseal System / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009538:Nicotine / Q000494:pharmacology*; D018722:Nicotinic Agonists / Q000494:pharmacology; D010913:Pituitary-Adrenal System / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology*; D013315:Stress, Psychological / Q000097:blood / Q000188:drug therapy / Q000503:physiopathology*; D014029:Tobacco Use Disorder / Q000097:blood / Q000503:physiopathology; D001615:beta-Endorphin / Q000378:metabolism
chemical_list: D018722:Nicotinic Agonists; D001615:beta-Endorphin; D009538:Nicotine; D000324:Adrenocorticotropic Hormone; D003345:Corticosterone