Effects of AT 1 and AT 2 Angiotensin Receptor Antagonists in Angiotensin II-Infused Rats
| Autor: | Rhian M. Touyz, Ernesto L. Schiffrin, Jin S. Li |
|---|---|
| Rok vydání: | 1998 |
| Předmět: |
medicine.medical_specialty
Pyridines Administration Oral Aorta Thoracic Blood Pressure Peptide hormone Kidney Receptor Angiotensin Type 2 Losartan Receptor Angiotensin Type 1 Angiotensin Receptor Antagonists Internal medicine Renin–angiotensin system Internal Medicine medicine Animals Infusions Parenteral Rats Wistar Receptor Receptors Angiotensin Angiotensin II receptor type 1 Chemistry Angiotensin II Body Weight Imidazoles Antagonist Heart Arteries Organ Size Coronary Vessels Rats Femoral Artery Endocrinology medicine.drug |
| Zdroj: | Hypertension. 31:487-492 |
| ISSN: | 1524-4563 0194-911X |
| DOI: | 10.1161/01.hyp.31.1.487 |
| Popis: | Angiotensin II (Ang II) appears to exert its contractile and growth-promoting effects through the AT 1 receptor subtype, whereas the AT 2 subtype may have growth-inhibitory and proapoptotic properties. Recently, some data have challenged this emerging concept. To clarify the role of AT 1 and AT 2 receptors, we treated Wistar rats that were infused with Ang II (120 ng/kg/min subcutaneously by osmotic minipump), with the AT 1 antagonist losartan (10 mg/kg/d in the drinking water) and the AT 2 antagonist PD123319 (30 mg/kg/d subcutaneously by osmotic minipump) for 21 days. At the end of the study, tail-cuff systolic blood pressure was 106±2.8 mm Hg in untreated rats and 108±2.0 mm Hg in rats infused with Ang II that received losartan, whereas it rose to 158±4.9 mm Hg in Ang II-infused rats and 158±3.0 mm Hg in rats infused with Ang II rats and PD123319 (the two latter groups P P PD123319 had a greater media, media cross-section, and media/lumen ratio than vessels from untreated or Ang II-infused rats treated with losartan. These results support the concept that in Wistar normotensive rats infused for 3 weeks with angiotensin II, growth in the heart, aorta, and coronary, renal, mesenteric, and femoral small arteries is mediated by the AT 1 receptor; the results show little evidence of a role of AT 2 receptors in mediating angiotensin II effects in this experimental paradigm. |
| Databáze: | OpenAIRE |
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