Angiotensin II-Induced Water Absorption Behavior

点击翻译按钮获取中文摘要

9310352 Propper Angiotensin II is a peptide antidiuretic hormone involved in maintaining water balance by acting both on peripheral targets to enhance water uptake across tissues and on the central nervous system to induce drinking behavior. Since water is essential for survival, understanding how this hormone enhances water-absorption is of utmost importance. The mechanism, however, by which angiotensin II acts in the brain is not well understood. While most vertebrates have a regular and predictable water supply, desert animals live in harsh conditions in which survival is dependent upon the ability to find, obtain and conserve water. These species have evolved mechanisms of water retention which allows them to survive under these uncharitable conditions. Dr. Propper has selected two species that differ in genetic background but live within the same austere environment. She will employ a combination of behavioral, neuroanatomical and endocrine techniques to determine the underlying mechanisms of Angiotensin 11 action. Dr. Propper will determine whether centrally administering this peptide induces water absorption behavior, and whether the behavior is blocked by antagonists to the receptor. Moreover, Dr. Propper will localize and characterize these angiotensin II receptors in the brain. Finally, she will determine the effects that dehydration has on central and peripheral receptor concentrations and correlate these changes with behavior in the natural environment. The results from this integrative work will provide new insights into the neural mechanisms underlying angiotensin action. Furthermore, since Dr. Propper is comparing species that differ in their genetic background, she will discover whether similar neuroendocrine mechanisms are employed to manage water balance in vertebrates in general. These findings may lead to a better understanding of how the neuroendocrine basis of adaptive behavior has evolved. ***