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.
Kantor
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Laboratory of Neurochemistry and Experimental Medicine, National Institute of Psychiatry and Neurology, PO Box 1, Huvosvolgyi ut 116, H-1021, Budapest, Hungary.
Anheuer
Z E
ZE
Bagdy
G
G
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