Characterization of angiotensin-II effects on cerebral and ocular circulation by noninvasive methods

British Journal of Clinical Pharmacology
K KrejcyL Schmetterer

Abstract

The role of the renin-angiotensin-system (RAS) in the cerebral and ocular circulation is still a matter of controversy. In vitro and animal data lead to partially contradicting results. However, direct investigation of locally generated angiotensin II (Ang II) in humans is not possible in vivo. Hence, we hypothesised that it might be possible to characterize local effects of Ang II by comparing systemic and local haemodynamic parameters during exogenous Ang II infusion. In a placebo-controlled, double-blind, two-way cross over study blood flow velocities in the middle cerebral and the ophthalmic artery and ocular fundus pulsations were measured during stepwise increasing doses of Ang II in 10 healthy subjects. Blood flow velocities were assessed by Doppler sonography, fundus pulsation amplitudes (FPA), which estimate local pulsatile ocular blood flow were measured by laser interferometry. Additionally, systemic blood pressure and pulse rate were measured. Ang II dose-dependently decreased resistive index (RI) and increased mean flow velocities (MFV) in both arteries. Fundus pulsation amplitude was dose-dependently decreased by Ang II, whereas mean arterial pressure (MAP) was significantly increased. Pulse pressure amplitude (PP...Continue Reading

Citations

Jun 18, 1999·American Journal of Ophthalmology·O FindlL Schmetterer
Oct 31, 1998·Brain Research. Molecular Brain Research·U BrändleT H Wheeler-Schilling
Oct 6, 2001·Progress in Retinal and Eye Research·L Schmetterer, K Polak
Jan 22, 2004·Journal of Ocular Pharmacology and Therapeutics : the Official Journal of the Association for Ocular Pharmacology and Therapeutics·Lijun GengSiv F E Nilsson
Mar 20, 2004·The British Journal of Ophthalmology·E PolskaL Schmetterer
Apr 27, 2000·The British Journal of Ophthalmology·O FindlL Schmetterer
Nov 30, 2013·Pharmacology & Therapeutics·Michael J Giese, Robert C Speth
Jan 8, 2014·The Journal of Physiology·Christopher K WilliePhilip N Ainslie
Sep 28, 2010·Experimental Eye Research·Doreen SchmidlLeopold Schmetterer
Sep 11, 2014·Medical Engineering & Physics·Tianne NumanPhilip N Ainslie
Oct 13, 2011·Acta Ophthalmologica·Ingeborg StalmansLeopold Schmetterer
Jul 26, 2002·Journal of Glaucoma·Tatiana SpicherJosef Flammer
Feb 27, 2001·Current Opinion in Ophthalmology·A Harris, C P Jonescu-Cuypers
Jan 29, 2011·Journal of the Renin-angiotensin-aldosterone System : JRAAS·Mohammadali M ShojaAaron A Cohen-Gadol
May 22, 1998·Stroke; a Journal of Cerebral Circulation·S DallingerL Schmetterer
Feb 13, 2003·Eye·K PolakL Schmetterer
Dec 6, 2005·American Journal of Physiology. Heart and Circulatory Physiology·Alexandra LukschLeopold Schmetterer
Aug 19, 2008·Acta Ophthalmologica·Esmeralda DelgadoLuis Silva-Carvalho
Mar 15, 2001·American Journal of Physiology. Heart and Circulatory Physiology·E PolskaL Schmetterer
Jun 11, 1999·The American Journal of Physiology·B KissL Schmetterer

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.