2006 Heart-Brain summit proceedings

Aging and the brain
renin-angiotensin system:
Insights from studies in transgenic rats

Debra I. Diz, PhD

Hypertension and Vascular Disease Center, Wake Forest University School
of Medicine
Winston-Salem, NC

ddiz@wfubmc.edu

 

Sherry O. KasperR, PhD

Hypertension and Vascular Disease Center, Wake Forest University School
of Medicine
Winston-Salem, NC

 

Atsushi Sakima, MD

Hypertension and Vascular Disease Center, Wake Forest University School of Medicine
Winston-Salem, NC

 

Carlos M. Ferrario, MD

Hypertension and Vascular Disease Center, Wake Forest University School
of Medicine
Winston-Salem, NC

ARTICLE INTRODUCTION

Aging is characterized by increased systolic blood pressure resulting from activation of the sympathetic nervous system, reduced vagal activity, and reduced vascular distensibility. Imbalances in sympathetic and parasympathetic outflow to vessels, heart, kidney, and other organs contribute to the increase in systolic blood pressure as well as the associated impairment in the gain of the baroreceptor reflex. The reduced heart rate variability linked to increased mortality in patients with cardiovascular disorders could be attributed in part to impaired reflex function. Alterations in reflex control of autonomic outflow may also contribute to the constellation of cardiovascular and metabolic changes known to accompany hypertension, especially during aging. Understanding the factors that regulate the function of the brainstem areas controlling autonomic outflow during aging is critical as the elderly proportion of the population continues to increase.

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