Brain angiotensin type-1 and type-2 receptors: cellular locations under normal and hypertensive conditions
| Autor: | Jacob A. Ludin, Eric G. Krause, Amy R. Alleyne, Meng Liu, Annette D. de Kloet, Colin Sumners, Shormista Kar, Zachary Winder, David J. Pioquinto, Vermali Rodriguez, Yuma T. Ortiz |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Physiology
Blood Pressure 030204 cardiovascular system & hematology Biology Baroreflex Receptor Angiotensin Type 2 Receptor Angiotensin Type 1 Article Rats Sprague-Dawley 03 medical and health sciences Mice 0302 clinical medicine Rats Inbred SHR Renin–angiotensin system Internal Medicine medicine Animals 030212 general & internal medicine Rats Wistar Receptor Cellular localization Neurons Microglia Solitary tract Colocalization Brain Neurogenic hypertension Cell biology Rats medicine.anatomical_structure Astrocytes Hypertension Cardiology and Cardiovascular Medicine |
| Zdroj: | Hypertens Res |
| ISSN: | 1348-4214 |
| Popis: | Brain angiotensin-II (Ang-II) type-1 receptors (AT1Rs), which exert profound effects on normal cardiovascular, fluid, and metabolic homeostasis, are overactivated in and contribute to chronic sympathoexcitation and hypertension. Accumulating evidence indicates that the activation of Ang-II type-2 receptors (AT2Rs) in the brain exerts effects that are opposite to those of AT1Rs, lowering blood pressure, and reducing hypertension. Thus, it would be interesting to understand the relative cellular localization of AT1R and AT2R in the brain under normal conditions and whether this localization changes during hypertension. Here, we developed a novel AT1aR-tdTomato reporter mouse strain in which the location of brain AT1aR was largely consistent with that determined in the previous studies. This AT1aR-tdTomato reporter mouse strain was crossed with our previously described AT2R-eGFP reporter mouse strain to yield a novel dual AT1aR/AT2R reporter mouse strain, which allowed us to determine that AT1aR and AT2R are primarily localized to different populations of neurons in brain regions controlling cardiovascular, fluid, and metabolic homeostasis. Using the individual AT1aR-tdTomato reporter mice, we also demonstrated that during hypertension induced by the administration of deoxycorticosterone acetate-salt, there was no shift in the expression of AT1aR from neurons to microglia or astrocytes in the paraventricular nucleus, a brain area important for sympathetic regulation. Using AT2R-eGFP reporter mice under similar hypertensive conditions, we demonstrated that the same was true of AT2R expression in the nucleus of the solitary tract (NTS), an area critical for baroreflex control. Collectively, these findings provided a novel means to assess the colocalization of AT1R and AT2R in the brain and a novel view of their cellular localization in hypertension. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink