CHARACTERIZATION OF VASCULAR MODULATORS IN THE PULMONARY CIRCUIT IN ECTOTHERMIC TETRAPODS

• Grant number: 24/13160-0
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: December 01, 2025
• End date: November 30, 2028
• Field of knowledge: Biological Sciences - Pharmacology - Cardiorenal Pharmacology
• Principal Investigator: Gilberto de Nucci
• Grantee: Samanta Aparecida Castro
• Host Institution: Faculdade de Ciências Médicas (FCM). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Studies on isolated tissues from mammals and reptiles have reported the presence and/or vasoactive function of endothelium-derived catecholamines, such as dopamine, noradrenaline and adrenaline, as well as recent findings (6-nitrodopamine - 6-ND, 6-cyanodopamine, 6-bromodopamine, 6-nitrodopa, and 6-nitroadrenaline). The presence of catecholamines in ectotherms and endotherms vasculature shows that endothelial-derived relaxing factors are conserved across evolutionarily process of vertebrates, and this characteristic may have potentially contributing to the survival of these animals in diverse environments. Although the presumed high importance of the pulmonary vascular modulation in most tetrapods due to their characteristic intracardiac blood shunts, our understanding of that system remains rather limited. Thus, this study aims to investigate the effects of endothelial catecholamines on the regulation of pulmonary vascular activity through a comprehensive analysis of different amphibian, non-crocodilian reptiles, and crocodilian species. Protocols will be performed to investigate basal release; determine concentration-response curves; quantify; and evaluate the effects of endothelial catecholamines. We will explore the role of the endothelium and the effects of 6-ND, 6-cyanodopamine, 6-bromodopamine, 6-nitrodopa e 6-nitroadrenaline on the vasoconstriction induced by dopamine, noradrenaline, adrenaline. Additionally, the association between nitric oxide and the release of 6-ND will be analyzed. Finally, the pathways of production and elimination of 6-ND will be investigated, and its possible receptors identified. The findings will elucidate the functional and adaptive significance of these endothelial factors in cardiovascular control. This project has capillarity in basic and applied areas and the right scope to support the start of an integrative line of research. (AU)