Pheromone-induced anorexia in male Syrian hamsters.
Transition from long days (LDs) to short days (SDs) triggers seasonal obesity in Syrian hamsters. We report here that SD-exposed males housed near females exhibit obesity resistance, episodic weight loss, and reduced adiposity. Negative energy balance is achieved by reduced eating, elevated motor activity, and increased caloric efficiency without metabolic compensation. Circulating leptin, insulin, testosterone, corticosterone, and cortisol are normal or reduced in obesity-resistant hamsters. When males are housed in chambers that block physical, visual, and auditory, but not pheromonal, signals from females, resistance to seasonal obesity persists. Moreover, inhalation of extracts from pheromone-releasing flank glands of females suppresses eating and weight gain in SD-exposed males. This novel phenomenon, pheromone-induced anorexia, shows that female pheromones play a critical role in the seasonal energy balance of male hamsters. These findings provide a model to study neural and endocrine mechanisms that underlie eating disorders.
Morgan
Caurnel
C
Vollum Institute for Advanced Biomedical Research and Oregon National Primate Research Center, Oregon Health and Science University, Portland, USA. cam2025@med.cornell.edu
Urbanski
Henryk F
HF
Fan
Wei
W
Akil
Huda
H
Cone
Roger D
RD
D000818:Animals; D006224:Cricetinae; D004435:Eating / Q000502:physiology*; D002149:Energy Intake; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D008297:Male; D008647:Mesocricetus / Q000502:physiology*; D009043:Motor Activity; D017440:Photoperiod; D012621:Seasons; D012724:Sex Attractants / Q000502:physiology*; D015430:Weight Gain
D012724:Sex Attractants