Distinctive responses in the medial amygdala to same-species and different-species pheromones.
Chemosignals related to reproductive and social status (pheromones) carry messages between opposite-sex and same-sex individuals in many species. Each individual must distinguish signals relevant to its own social behavior with conspecifics from signals used by other (heterospecific) species relevant to their social behavior. In male hamsters, the medial amygdala responded in a categorically different way to conspecific stimuli (socially relevant) and heterospecific stimuli (not socially relevant but serving similar purposes for other species), and may play an important role in this decision. Immediate-early gene responses to conspecific chemosignals and heterospecific chemosignals were characteristically different. The categorical responses, generated by chemosensory input from the vomeronasal organ and (probably) GABA inhibition within the amygdala, were not apparent at more peripheral sensory levels. This is the first evidence for an important role of the amygdala, a limbic structure known to be involved in social and emotional behavior, in discrimination of species specificity in chemosignals.
Meredith
Michael
M
Program in Neuroscience and Department Biological Science, Florida State University, Tallahassee, Florida 32306-4340, USA. mmered@neuro.fsu.edu
Westberry
Jenne M
JM
D000281:Administration, Intranasal; D000600:Amino Acids, Dicarboxylic / Q000494:pharmacology; D000679:Amygdala / Q000187:drug effects* / Q000502:physiology; D000818:Animals; D002415:Cats; D006224:Cricetinae; D004558:Electric Stimulation; D005260:Female; D008297:Male; D008647:Mesocricetus; D051379:Mice; D009474:Neurons / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D009833:Olfactory Pathways / Q000187:drug effects / Q000502:physiology; D010675:Pheromones / Q000302:isolation & purification / Q000494:pharmacology*; D018094:Receptors, Metabotropic Glutamate / Q000819:agonists; D013045:Species Specificity; D014556:Urine; D014621:Vagina / Q000737:chemistry; D019147:Vomeronasal Organ / Q000502:physiology; D019287:Zinc Sulfate / Q000008:administration & dosage / Q000494:pharmacology; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D000600:Amino Acids, Dicarboxylic; D010675:Pheromones; D018094:Receptors, Metabotropic Glutamate; C108822:metabotropic glutamate receptor 2; C035261:(alpha-carboxycyclopropyl)glycine; D005680:gamma-Aminobutyric Acid; D019287:Zinc Sulfate