Paternal Retrieval Behavior Regulated by Brain Estrogen Synthetase (Aromatase) in XXXX Sires that Engage in Communicative Interactions with Pairmates.

@entity1 @entity172 @entity251 @entity4819 @entity19 @entity342
Parental behaviors involve complex social recognition and memory processes and interactive behavior with @entity1 that can greatly facilitate healthy @entity1 family life. Fathers play a substantial role in @entity1 care in a small but significant number of mammals, including @entity1 . However, the brain mechanism that controls male parental behavior is much less understood than that controlling female parental behavior. Fathers of non-monogamous laboratory ICR @entity19 are an interesting model for examining the factors that influence paternal responsiveness because sires can exhibit maternal-like parental care (retrieval of pups) when separated from their pups along with their pairmates because of olfactory and auditory signals from the dams. Here we tested whether paternal behavior is related to femininity by the aromatization of @entity251 . For this purpose, we measured the immunoreactivity of aromatase [ @entity4819 ( @entity4819 )], which synthesizes @entity172 from @entity342 , in nine brain regions of the sire. We observed higher levels of aromatase expression in these areas of the sire brain when they engaged in communicative interactions with dams in separate cages. Interestingly, the number of nuclei with aromatase immunoreactivity in sires left together with maternal mates in the home cage after pup-removing was significantly larger than that in sires housed with a whole family. The capacity of sires to retrieve pups was increased following a period of 5 days spent with the pups as a whole family after parturition, whereas the acquisition of this ability was suppressed in sires treated daily with an aromatase inhibitor. The results demonstrate that the dam significantly stimulates aromatase in the male brain and that the presence of the pups has an inhibitory effect on this increase. These results also suggest that brain aromatization regulates the initiation, development, and maintenance of paternal behavior in the ICR male @entity19 .
