Vasopressin deficiency abolishes a sexually dimorphic behavior in Brattleboro rats.
The role of vasopressin (VP) in a sexually dimorphic behavior, the extinction of a conditioned taste aversion, was investigated in male and female rats of three different genotypes. This behavior was examined with a two bottle test in the wild-type Long-Evans (LE) rats, and then in partially VP deficient heterozygous (HET-BB) and completely VP deficient homozygous (HO-BB) Brattleboro rats. In Experiment 1, non-deprived male and female LE rats were given aversions to a sucrose solution by pairing it with a LiCl injection. The rate of extinction of the aversion upon reexposure to ad lib sucrose solution was examined and observed to be sexually dimorphic. Female LE rats extinguished at a significantly more rapid rate than males. Experiment 2 compared HET-BB and HO-BB male and female rats using the same paradigm. Neither of these VP-deficient groups showed sexual dimorphism of the extinction behavior. The data suggest that intact VP levels are necessary to observe the expression of this sexually dimorphic behavior.
Brot
M D
MD
Department of Psychology, University of Washington, Seattle 98195.
Bernstein
I L
IL
Dorsa
D M
DM
D000818:Animals; D001143:Arousal / Q000502:physiology*; D001362:Avoidance Learning / Q000502:physiology; D001931:Brain Mapping; D003214:Conditioning, Classical / Q000502:physiology; D005108:Extinction, Psychological / Q000502:physiology; D005260:Female; D007031:Hypothalamus / Q000502:physiology; D008032:Limbic System / Q000502:physiology; D008297:Male; D051381:Rats; D011910:Rats, Brattleboro; D012727:Sex Characteristics; D013649:Taste / Q000502:physiology; D014667:Vasopressins / Q000502:physiology*
D014667:Vasopressins