Psychiatry Research, 33 : 1-10 Elsevier Altered Norepinephrine Regulation in Bulimia: Effects of Pharmacological Challenge With lsoproterenol David T. George, Walter H. Kaye, David S.· Goldstein, Timothy D. Brewerton, and David C. Jimerson Received September 15, 1989; revised version received February 9, 1990; accepted April 8. 1990. Abstract. While abnormalities in central norepinephrine regulation may contribute to abnormal eating patterns in bulimia nervosa, alterations in function of the peripheral sympathetic nervous system could contribute to the decreased metabolic rate and increased anxiety responses previously reported in these patients. To assess ,8-adrenergic receptor sensitivity in bulimic patients, we studied cardiovascular and hormonal responses to acute pharmacological challenge with intravenously administered isoproterenol. In comparison to healthy controls, binge-abstinent bulimic patients had significantly reduced mean baseline plasma norepinephrine level, pulse rate, and systolic blood pressure, and significantly increased chronotropic responses to isoproterenol infusion. Decreased sympathoneural activity may contribute to a tendency for bulimic patients to maintain body weight despite low caloric intake. Key Words. Bulimia, adrenergic receptor, norepinephrine, sympathetic nervous system, isoproterenol. The syndrome of bulimia nervosa encompasses a constellation of recurrent episodes of binge eating, discontent with body weight and appearance, and preoccupation with regulation of caloric intake. Preclinical studies have demonstrated an important role for central nervous system (CNS) norepinephrine (NE) pathways in the modulation of feeding behaviors (Aston-] ones and Bloom, 1981; Leibowitz, 1970, 1980; Bendotti et al., 1986). Dysregulation of hypothalamic NE, perhaps in association with alteration in other neurotransmitters (such as serotonin) that modulate eating behaviors, could contribute to these symptoms (Jimerson et al., 1988), as well as to symptoms of depression and anxiety, which are common in Preliminary results of this study were presented at the Annual Meeting of the Society of Biological Psychiatry, Dallas, TX, May, 1985. David T. George, M.D., is Senior Staff Fellow, Laboratory of Clinical Studies, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD . Walter H. Kaye, M.D., is Program Director, Inpatient Eating Disorders Unit, Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA. David S. O'bldstein, M.D., Ph.D., is Senior Investigator, Hypertension-Endocrine Branch, National Heart, Lung, Blood Institute, Bethesda, MD. Timothy D. Brewerton, M.D ., is Associate Professor of P;;ychiatry, Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC. David C. Jimerson, M.D., is Associate Professor of Psychiatry, Harvard Medical School, and Director of Research, Department of Psychiatry, Beth Israel Hospital, Boston, MA . (Reprint requests to Dr. D.C. Jimerson, Dept. of Psychiatry, Beth Israel Hospital, 330 Brookline Ave., Boston, MA 02215, USA.) 0165-1781 /90/$03.50 1990 Elsevier Scientific Publishers Ireland Ltd.