| Summary: | In certain species, puberty is thought to be a period of susceptibility to
various stressors, resulting in pathological behavioral and physiological changes
subsequent to exposure during this period. However, juvenile male golden
hamsters appear to be fairly resilient to pubertal stress, as compared to adult
hamsters and many other species. In these experiments, repeatedly stressed
juvenile male hamsters were found to be avoidant of aggressive adult male social
stimuli, but did not display anxious behavior outside of a social context. In
addition, several long-term changes in neural activity were associated with social
stress during early puberty. The medial preoptic area and medial preoptic
nucleus, and ventral tegmental area showed decreased neural activity in
subjugated juveniles than in naïve individuals. Since these brain areas are
involved in the expression of motivated behaviors, specifically sexual behavior,
and reward pathways, we next investigated sexual behavior in virgin juveniles.
When placed in a confined space with receptive females, consummatory
behavior in subjugated juveniles was similar to those observed in naive juveniles.
Appetitive aspects of sexual behavior were also tested in a Y-maze to allow
subjects to choose whether to approach a social stimulus. When given a choice
between a sexually receptive and non-receptive female social stimulus, socially
stressed individuals showed anxiety related behaviors and did not show a
preference. However, naïve hamsters preferred the non-receptive female.
Interestingly, this effect was less significant in naïve animals tested during late
puberty and early adulthood, and a preference for sexually receptive females
was not observed. In addition, stressed hamsters tested with harnessed females
at mid-puberty were slower to approach females, indicating altered motivation to
approach adult conspecifics. This research is unique in that it is the first to
suggest the disconnect between the development of consummatory and
appetitive aspects of sexual behavior. Together, these data examine the effects
of stress on the development of pubertal social behaviors. === text
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