Abstract:

Rat maternal behavior is a complex instinct behavior, which can be used as an effective model to study how drugs influence social behavior. Humans and animals have many similar characteristics. Many clinically used antipsychotic drugs such as haloperidol, clozapine, risperidone, olanzapine, quetiapine, aripiprazole and amisulpride disrupt maternal responses (e.g. pup retrieval, pup licking and nest building) to various extents. We present a summary of recent studies on the behavioral effects and neurobiological mechanisms of antipsychotic action on maternal behavior in rats. We also discuss the potential clinical implications of such preclinical studies for the understanding of the quality of human maternal care in schizophrenic patients who are treated with antipsychotic medications. We argue that antipsychotic drugs disrupt active maternal responses primarily by suppressing maternal motivation. Atypical drugs-induced sedation also contributes to their disruptive effects, especially that on pup nursing. Dopamine D₂receptors and serotonin 5-HT_2A/2C receptors are critically involved in the maternal disruptive effects of antipsychotic drugs, with D₂ receptors contributing more to typical antipsychotic-induced disruptions, while 5-HT_2A/2C receptors contributing more to atypical drug-induced disruption. The nucleus accumbens shell-related reward circuitry is an essential neural network in the mediation of the behavioral effects of antipsychotic drugs on maternal behavior. This line of research is not only important for enhancing our understanding of the neurochemical basis of maternal behavior, but also valuable for understanding the complete spectrum of therapeutic and side-effects of antipsychotic treatment. Studying the behavioral effects of antipsychotic drugs on maternal behavior could also help us understand the eAxtent and mechanisms of impacts of antipsychotic medications on human maternal care. This knowledge may facilitate the development of effective behavioral or other intervening strategies to help patients coping with such undesirable effects.

Key words: maternal behavior, antipsychotic drugs, rats, dopamine D₂ receptor, serotonin 5-HT_2A/2C receptor, nucleus accumbens