The Melanin-Concentrating Hormone as a regulator of maternal behavior in Long-Evans Rats (Rattus norvegicus): An Immunohistochemical, Endocrine, and Genetic Study

• Grant number: 24/14522-3
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: January 01, 2025
• End date: December 31, 2026
• Field of knowledge: Biological Sciences - Morphology
• Principal Investigator: Jackson Cioni Bittencourt
• Grantee: Heriberto Barbosa Moyano
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Melanin-concentrating hormone (MCH) is a neuropeptide that regulates motivated behaviors and sensory integration. Recently, its regulatory functions in maternal behaviors have been investigated, although these regulatory effects still need to be fully understood. This research project is based on previous findings that emphasize the importance of the ventromedial preoptic area (MPOAvm) in the expression of maternal behaviors and the exclusive presence of MCH in females during lactation in this hypothalamic area. The following questions guide this research: What is the relationship between MCH and maternal behaviors? Are the regions positive for MCH immunohistochemistry tests (MCH-ir) in the MPOAvm the result of neurogenesis/neuroplasticity during lactation, and are they specific to the first birth? Is the presence of a litter fundamental for the expression of MCH in the MPOAvm? Do the number of cells MCH-ir+ and the MCH precursor gene (ppMCH) expression in the MPOAvm vary between primiparous and multiparous females? Does MPOA have Mcrh1 receptors, and does this expression vary to the number of births and the day after birth? Do MCH plasma levels vary throughout lactation similarly to prolactin or oxytocin? Do MCH plasma levels correlate with the expression of maternal behaviors and the postpartum day? These questions will guide this research in exploring the relationship between MCH and maternal behavior and understanding the dynamics of brain regions associated with neurogenesis during the lactation period, considering different reproductive experiences.