Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6809758 | Neurobiology of Aging | 2012 | 7 Pages |
Abstract
Impaired neural transduction of barosensory vessel stretch into vagal outflow is a primary determinant of reduced cardiovagal baroreflex gain with human aging. We set out to determine whether age-related reductions in this neural component of the baroreflex might be offset by enhancing the central integration/efferent responsiveness of the neural arc. Low vagotonic doses of atropine were employed to enhance central neural outflow and peripheral sinus node effects. Baroreflex gain and its neural and mechanical components were pharmacologically assessed before and after intravenous vagotonic atropine in 16 older and 14 young healthy subjects. Vagotonic atropine increased cardiovagal baroreflex gain (â¼30%) and its neural component (â¼20%) in older but not young individuals. Moreover, the atropine-induced increases in integrated gain and in its neural component were inversely related to baseline levels. Thus, age-related neural deficits in the baroreflex arc appear to play a determining role in reduced cardiovagal baroreflex gain with age and the compromised neural baroreflex function can be acutely improved by a single pharmacologic intervention.
Keywords
Related Topics
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Biochemistry, Genetics and Molecular Biology
Ageing
Authors
Carine C. Callegaro, J. Andrew Taylor,