Figure 8. Pair bonding alters DA and dynorphin/KOR systems within the ventral striatum.
(a) Non-pair bonded prairie voles readily approach novel conspecifics and have lower levels of stimulated DA release as well as Drd1 and Pdyn mRNA expression within the ventral striatum. (b) Following the establishment of a pair bond, male and female prairie voles aggressively reject novel conspecifics and the ventral striatum undergoes a dramatic reorganization. Specifically, pair bonding enhances DA release within the NAc shell as well as up-regulates Drd1 as well as Pdyn within the ventral striatum of both males and females. Pair bonded males also show an additional decrease in KOR binding within the NAc shell.