Chronic angiotensin II AT1 receptor blockade increases cerebral cortical microvessel density. Am J Physiol Heart Circ Physiol 2006 Feb;290(2):H512-6
Date
10/04/2005Pubmed ID
16199473DOI
10.1152/ajpheart.01136.2004Scopus ID
2-s2.0-33644865215 (requires institutional sign-in at Scopus site) 39 CitationsAbstract
Angiotensin II is known to stimulate angiogenesis in the peripheral circulation through activation of the angiotensin II type 1 (AT1) receptor. This study investigated the effect of angiotensin receptor blockade on cerebral cortical microvessel density. Rats (6-7 wk old, n = 5-17) were instrumented with femoral arterial and venous indwelling catheters for arterial blood pressure measurement and drug administration. Rats were treated for 3 or 14 days with the AT1 receptor blocker losartan (50 mg/day in drinking water) or vehicle. Brains were sectioned and immunostained for CD31, and microvessel density was measured. Treatment with losartan for 3 or 14 days resulted in a slight decrease in mean arterial blood pressure (3 days, 92 +/- 1 mmHg; and 14 days, 99 +/- 2 mmHg) compared with vehicle (109 +/- 3 and 125 +/- 4 mmHg, respectively). A furosemide + captopril 14-day treatment group was added to control for the blood pressure change (96 +/- 3 mmHg). Microvessel density increased in groups treated with losartan for 14 days (429 +/- 13 vessels/mm2) compared with vehicle (383 +/- 11 vessels/mm2) but did not change with furosemide + captopril (364 +/- 7 vessels/mm2). Thus AT1 receptor blockade for 14 days resulted in increased cerebral microvessel density in a blood pressure-independent manner.
Author List
Munzenmaier DH, Greene ASMESH terms used to index this publication - Major topics in bold
Angiotensin II Type 1 Receptor BlockersAnimals
Antihypertensive Agents
Blood Pressure
Blood Vessels
Captopril
Cerebral Cortex
Diuretics
Drug Administration Schedule
Drug Combinations
Furosemide
Losartan
Male
Microcirculation
Rats
Rats, Sprague-Dawley
Time Factors
