Renal microvascular actions of angiotensin II fragments
| Autor: | Geert-Jan Tangelder, Michiel H. van Wijhe, Piet M. ter Wee, Ton A. van Lambalgen, William F. van Rodijnen |
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| Rok vydání: | 2002 |
| Předmět: |
Male
medicine.medical_specialty Afferent arterioles Physiology Vasodilation Hydronephrosis In Vitro Techniques Receptor Angiotensin Type 2 Receptor Angiotensin Type 1 Renal Circulation Microcirculation Rats Sprague-Dawley Internal medicine Renin–angiotensin system medicine Animals Vasoconstrictor Agents Kidney Receptors Angiotensin Renal circulation Chemistry Angiotensin II Peptide Fragments Rats medicine.anatomical_structure Endocrinology cardiovascular system Angiotensin I hormones hormone substitutes and hormone antagonists Interlobular arteries |
| Zdroj: | American Journal of Physiology-Renal Physiology. 283:F86-F92 |
| ISSN: | 1522-1466 1931-857X |
| DOI: | 10.1152/ajprenal.00121.2001 |
| Popis: | In the present study, we investigated renal microvascular responses to ANG-(1–7) and ANG IV. Diameter changes of small interlobular arteries, afferent arterioles, and efferent arterioles were assessed by using isolated perfused hydronephrotic rat kidneys. ANG-(1–7) and ANG IV concentration dependently decreased the diameters of all investigated renal microvessel, however, with a much lower potency than ANG II. The ANG II type 1 receptor blocker irbesartan completely reversed the responses to ANG-(1–7) and ANG IV, whereas the ANG II type 2 receptor blocker PD-123319 had no effect. Both ANG-(1–7) and ANG IV failed to alter renal microvascular constriction induced by ANG II. In addition, subnanomolar concentrations of ANG-(1–7) had no effect on the myogenic-induced tone of interlobular arteries and afferent arterioles. Thus our data indicate that at high concentrations, ANG-(1–7) and ANG IV are able to activate the ANG II type 1 receptor, thereby inducing renal microvascular constriction. The failure of ANG-(1–7) and ANG IV to reduce ANG II- and pressure-induced constrictions suggests that these fragments do not exert a vasodilator and/or ANG II antagonistic action in the kidney. |
| Databáze: | OpenAIRE |
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