Journals of Gerontology Series A: Biological Sciences and Medical Sciences, Vol 51, Issue 6 B454-B460, Copyright © 1996 by The Gerontological Society of America
Effects of captopril and propranolol on cognitive function and cerebral blood flow in aged hypertensive rats
MH Skinner, DX Tan, M Grossmann, MT Pyne and RK Mahurin
Department of Pharmacology, University of Texas Health Science Center, San Antonio, USA.
Chronic hypertension has been reported to produce adverse cognitive effects
in elderly individuals, perhaps by altering central nervous system
hemodynamics. The beneficial or adverse effects of antihypertensive drugs
on these processes are not well understood. We examined the effects of
captopril (90 mg/kg/day) and propranolol (80 mg/kg/day) on cognitive
function and brain blood flow in hypertensive and normotensive rats.
Cognitive function was assessed by the Morris water maze, and regional
brain blood flow was measured by the [14C]iodoantipyrine method.
Nineteen-month-old propranolol-treated hypertensive rats exhibited poorer
performance (p < .05) than control rats and had lower brain blood flows,
particularly in white matter regions (p < .01). Captopril-treated
hypertensive rats did not differ significantly from control rats with
regard to either cognitive performance or brain blood flow. In the
normotensive rats, there were no effects of either drug on cognitive
performance or brain blood flow. Thus, blood pressure reduction by
propranolol but not captopril has an adverse effect on cognitive function
and brain blood flow in hypertensive rats.
