High social anxiety and low aggression in Fawn-Hooded rats.
The Fawn-Hooded (FH) rat strain, with well-documented changes in their serotonergic and noradrenergic systems, is a putative genetic model for some neuropsychiatric disorders like depression, alcohol abuse, and anxiety. Because social phobia frequently occurs in combination with these disorders and there are no social anxiety-related data in FH rats in the literature, we measured the behavior of FH rats in the social interaction test. In addition, the effects of the anxiogenic Serotonin-2C (5-HT2C) receptor agonist, m-chlorophenylpiperazine (m-CPP), were studied. Male FH, Wistar (W), and Sprague-Dawley (SD) rats were used in two different test conditions of the social interaction test: the high light, unfamiliar arena, associated with high anxiety, and the low light, familiar arena, associated with low anxiety-like behavior. All social behaviors were markedly diminished in FH rats that suggested higher anxiety in these animals. Total social interaction time was reduced by 60-70% in FH rats compared either to W or SD rats under high light, unfamiliar or low light, familiar conditions, respectively. Aggressive behavior was reduced at least by 85% in FH rats. Locomotor activity and exploratory behavior were only minimally, in most comparisons, not significantly affected in FH rats. Total social interaction time, aggression, and locomotor activity were decreased, and self-grooming increased by m-CPP (0.5 mg/kg, ip) in all three strains. m-CPP decreased total social interaction time thus, caused anxiety most efficiently in FH rats (reduced by 69%, 50%, and 55% in FH, W, and SD rats, respectively), but other effects of the drug were similar in the three strains. Our studies provide evidence that the FH rat strain may be a genetic model of social phobia or other anxiety disorders with impaired social behavior.
Laboratory of Neurochemistry and Experimental Medicine, National Institute of Psychiatry and Neurology, PO Box 1, Huvosvolgyi ut 116, H-1021, Budapest, Hungary.
S
S
Kantor
Z E
ZE
Anheuer
G
G
Bagdy
D000374:Aggression / Q000523:psychology*; D000818:Animals; D001007:Anxiety / Q000235:genetics* / Q000523:psychology; D007398:Interpersonal Relations; D008029:Lighting; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D017207:Rats, Sprague-Dawley; D012919:Social Behavior; D012931:Social Environment