Dopamine D2 receptor agonists prevent impairment of maternal care in lipopolysaccharide-induced postpartum depression model mice

Postpartum depression is a prevalent mental disorder that affects mothers and has adverse effects on families. The decline in parenting quality associated with postpartum depression raises concerns about the adverse impact on children. Therefore, it is desirable to prevent deterioration in parenting quality in depressed mothers. This study aims to investigate whether antidepressive agents can prevent the decline in parenting quality associated with postpartum depression. Maternal care and sucrose palatability were evaluated in postpartum female mice with intraperitoneal lipopolysaccharide (LPS) administration 24 hr before testing. In the maternal care test, LPS increased the latency to retrieving pups into the nest and to crouching over the pups in the nest and decreased the duration for crouching over the pups. Furthermore, in the sucrose preference test, the ratio of sucrose intake decreased. Next, dopamine D2 receptor agonists (quinpirole and bromocriptine), a selective serotonin reuptake inhibitor (fluoxetine), or a tricyclic antidepressant (imipramine) was intraperitoneally administered 30 min before LPS administration. Treatment with quinpirole and bromocriptine, but not fluoxetine and imipramine, decreased the crouching latency and increased the crouching duration in LPS-treated postpartum females. On the other hand, all of the antidepressive agents did not affect the ratio of sucrose intake. Furthermore, the dopamine D2 receptor antagonist haloperidol disturbed the effects of quinpirole and bromocriptine on maternal care. These results indicate that dopamine D2 receptor agonists can prevent the decline in parenting quality via dopamine D2 receptor in LPS-induced postpartum depression model mice.