Adolescent activity-based anorexia increases anxiety-like behavior in adulthood.
Activity-based anorexia is a paradigm that induces increased physical activity, reduced food intake, and heightened activity of the hypothalamic-pituitary-adrenal axis in adult rats. To investigate whether experience with activity-based anorexia produced enduring effects on brain and behavior, female adolescent rats experienced activity-based anorexia during adolescence and were tested in adulthood for anxiety-like behavior on an elevated plus maze and in an open field. Analysis of elevated plus maze and open field behavior in adulthood revealed that rats that experienced activity-based anorexia during adolescence, but not rats that were simply food restricted, displayed increased anxiety-like behavior in adulthood. Plasma corticosterone and expression levels of corticotropin-releasing hormone mRNA in the hypothalamic paraventricular nucleus and in the central nucleus of the amygdala were significantly elevated in adult rats that had undergone activity-based anorexia in adolescence in response to the open field exposure, as compared to control rats. These data demonstrate enduring effects of adolescent activity-based anorexia on anxiety-like behavior and neuroendocrine factors critical in stress responsivity in adulthood. Furthermore, we demonstrate that activity-based anorexia during adolescence serves as a model whereby prolonged anxiety is induced, allowing for evaluation of the behavioral and neural correlates of mediating anxiety-like behaviors in adulthood.
Kinzig
Kimberly P
KP
Department of Psychological Sciences, Ingestive Behavior Research Center, Purdue University, West Lafayette, IN 47907, USA. kkinzig@psych.purdue.edu
Hargrave
Sara L
SL
D000367:Age Factors; D000679:Amygdala / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D000855:Anorexia / Q000503:physiopathology*; D001007:Anxiety / Q000503:physiopathology*; D001522:Behavior, Animal / Q000502:physiology*; D001835:Body Weight / Q000502:physiology; D003345:Corticosterone / Q000097:blood; D003346:Corticotropin-Releasing Hormone / Q000235:genetics / Q000378:metabolism; D004195:Disease Models, Animal; D004435:Eating / Q000502:physiology; D005106:Exploratory Behavior / Q000502:physiology; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology; D008124:Locomotion / Q000502:physiology; D018782:Maze Learning / Q000502:physiology; D010286:Paraventricular Hypothalamic Nucleus / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011863:Radioimmunoassay / Q000379:methods; D051381:Rats; D020318:Rats, Long-Evans
D012333:RNA, Messenger; D003346:Corticotropin-Releasing Hormone; D003345:Corticosterone