Removing sex-different vasopressin cells in bed nucleus of the stria terminalis (BNST) alters social behavior
In males, selectively lesioning BNST vasopressin (VP) cells reduced social investigation of other males and increased urine marking in the presence of a live female, without altering ultrasonic vocalizations, aggression, copulation, anxiety, or investigation of females. In females, which have significantly fewer VP cells in the BNST, cell removal influenced copulatory behavior but otherwise had minimal effects on social behavior and communication, indicating that these cells contribute to sex differences in social behavioral function. Complimentary projects using RNA-interference to reduce vasopressin are ongoing.
Removing sex-different vasopressin cells in bed nucleus of the stria terminalis (BNST) alters positive hedonic states and impairs recognition of social novelty
Circumstantial evidence supports the hypothesis that the sexually dimorphic vasopressin (VP) innervation of the brain tempers sickness behavior in males. Here we test this hypothesis directly, by comparing induced sickness behavior in animals with or without ablations of BNST VP cells, a major source of sexually dimorphic VP in the brain. Deletion of these cells had minimal effects on sickness behavior in males or female mice, but did increase consumption of sucrose (a measure of positive hedonic state) in both sexes. Males, but not females, with cell ablations showed impairment in recognition of social novelty compared to control mice. These data confirm that BNST VP cells control social behavior in a sexually dimorphic way, but do not play a critical role in sickness behavior.
Tracing monosynaptic inputs and outputs of sex-different vasopressin cells in bed nucleus of the stria terminalis (BNST) and medial amygdala
We are using modern viral mapping techniques to identify the monosynaptic inputs and outputs of BNST and medial amygdala VP cells (shown: rabies virus-labeled input cell in lateral hypothalamus)
Using optogenetic and chemogenetic techniques to identify acute effects of increasing or decreasing VP cell activity
We are currently using optogenetic and chemogenetic techniques to increase or decrease activity of VP cells in BNST and medial amygdala (top: ChR2-mediated excitation of BNST VP cells in vitro; bottom: stGTACR2-mediated inhibition of BNST VP cells)
Removing vasopressin cells in the paraventricular nucleus of the hypothalamus (PVN) increases female social investigation and male anxiety
Deletion of PVN vasopressin (VP)-expressing cells increased social investigation in females, but not in males. However, in males but not in females, these lesions increased non-social anxiety-related behaviors in the elevated-plus maze. These results therefore point at differential involvement of PVN VP-expressing cells in the context of social and emotional behavior in the two sexes, which may contribute to sex differences in social communication and anxiety disorders.
We have also found that PVN VP ablation exacerbated sickness behavior in both sexes, but with a stronger effect on males. This suggests that PVN VP contributes to the change in motivated behaviors during sickness and may help promote recovery from infection (in press).
Does removing vasopressin cells from the suprachiasmatic nucleus of the hypothalamus (SCN) alter social and emotional behavior?
We are currently investigating the effects of deleting SCN vasopressin (VP)-expressing cells on social and emotional behavior in both sexes.