Neural circuits for oxytocin release and maternal behavior

• Applicant: Dr. Silvana Valtcheva
• Subject Area: Cognitive, Systems and Behavioural Neurobiology ; Molecular Biology and Physiology of Neurons and Glial Cells
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 467461831

Maternal care is critical for child survivor. Early mother-infant relationships have long-term effects on the cognitive, behavioral, and emotional development, and overall health of the offspring. Various sensory cues from the newborn are tremendously efficient in triggering parental responses in new mothers. Deficits in maternal care can lead to deleterious long-term effects on child development. This makes research on neural networks involved in maternal reactivity to infant cues of tremendous clinical relevance.Prior research has described the importance of the neurohormone oxytocin (OT) in lactation and other maternal behaviors in rodents and humans. Release of OT from the hypothalamus is triggered by peripheral somatosensory stimulation during nursing or labor. However, our understanding about what non-tactile sensory cues from infants can activate OT neurons to release OT and promote other maternal behavior is limited. Recent studies have shown that OT neurons in maternal mice receive auditory projections from the thalamus and are activated by vocalizations from pups. Nonetheless, it is unknown what mechanisms control the activity of OT neurons, how different sensory cues from infants promote OT release and maternal behavior, and how synaptic plasticity during the lactation period affects the sensitivity to these infant signals.This project investigates the synaptic mechanisms and neural circuits underlying the processing of infant cues in hypothalamic OT neurons to mediate OT release and maternal behavior in mice. To address this, we will combine state-of-the-art approaches including in vivo and in vitro electrophysiology, fiber photometry, mouse behavior, viral tracing approaches, opto- and chemogenetics. Specifically, we will investigate: (1) If OT neurons integrate multisensory pup cues? (2) What are the synaptic circuits controlling the activity of OT neurons and maternal behavior? (3) Which components of these mechanisms are innate or learned? We will start by elucidating the neural circuits controlling multisensory integration of infant stimuli in the maternal hypothalamus ensuring fast and reliable parental responses. We will describe the sensory inputs to the hypothalamus and investigate the in vivo responses of OT neurons to different stimuli from pups. We will link the activity of OT neurons to OT release in vivo. We will further investigate how pup cues modulate synaptic plasticity in OT neurons. Finally, by exploring what aspects of OT neuronal responses are hardwired or experience-dependent, we will gain new understanding about the interactions of innate and learned mechanisms in brain circuits important for child care. Studying the neurobiological basis of maternal care will advance our understanding not only about the parental brain but also about the foundation of the mammalian social behavior itself.

• DFG Programme: Independent Junior Research Groups
• International Connection: USA
• Major Instrumentation: Multi-Purpose Electrophysiology Set-up ; Patch-Clamp Set-Up with Microscope
• Instrumentation Group: 5040 Spezielle Mikroskope (außer 500-503)
• Cooperation Partners: Professor Robert C. Froemke, Ph.D.; Professor Hyungbae Kwon, Ph.D.