Serotonin 5-HT1A and 5-HT3 receptors in an impulsive-aggressive phenotype.
In adult male hamsters, individual differences in offensive aggression are correlated with differences in impulsive choice and decreased serotonin (5-HT) innervation. As serotonin 1A (5-HT1A) receptors participate in the inhibition of aggression, whereas 5-HT3 receptor activation facilitates aggression, the authors hypothesized that differences in their expression are associated with differences in behavior. The authors confirmed previous behavioral associations, using a delay-discounting paradigm with various delays, as high-aggression (H-Agg) hamsters preferred the immediate-reward lever over the delayed-reward lever under most delays, compared with low-aggression (L-Agg) hamsters. Although the authors observed a greater density of 5-HT1A receptor immunoreactivity in H-Agg hamsters within several areas, it appears to be related to a lack of serotonin release, as supported by further observations of decreased immunoreactive perikarya and 5-HT1A receptors in fluoxetine-treated hamsters. Also, 5-HT3 receptor density was greater in H-Agg hamsters within select areas. The data indicate a convergence of impulsive and aggressive characteristics to one phenotype that is associated with various aspects of serotonin function, such as serotonin release and differential expression of 5-HT1A and 5-HT3 receptors.
Cervantes
M Catalina
MC
Department of Psychology, Institute for Neuroscience, University of Texas at Austin, Austin, TX 78712, USA. catalinacervantes@mail.utexas.edu
Delville
Yvon
Y
D000374:Aggression / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D003213:Conditioning, Psychological; D006224:Cricetinae; D005473:Fluoxetine / Q000494:pharmacology; D007150:Immunohistochemistry; D007175:Impulsive Behavior / Q000503:physiopathology*; D008297:Male; D008647:Mesocricetus; D010641:Phenotype; D010784:Photomicrography; D044282:Receptor, Serotonin, 5-HT1A / Q000378:metabolism*; D044406:Receptors, Serotonin, 5-HT3 / Q000378:metabolism*; D012201:Reward; D012701:Serotonin / Q000378:metabolism; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology; D013997:Time Factors
D005473:Fluoxetine; D044282:Receptor, Serotonin, 5-HT1A; D044406:Receptors, Serotonin, 5-HT3; D012701:Serotonin; D017367:Selective Serotonin Reuptake Inhibitors