Effects of an angiotensin-converting enzyme inhibitor, lisinopril, on cerebral blood flow autoregulation in healthy volunteers.
The effects of a single oral dose (20 mg) of lisinopril on systemic, carotid (pulsed Doppler), and cerebral (middle cerebral artery, transcranial Doppler) hemodynamics have been investigated over an 8-h period in eight healthy volunteers in a double-blind placebo-controlled crossover study. In addition, cerebral vasodilatory reserve was measured (acetazolamide test). Lisinopril did not affect systemic hemodynamics but it increased both common carotid artery blood flow (+26.2%, p < 0.01) and diameter (+4.5%, p < 0.05) after 8 h. Lisinopril did not affect middle cerebral artery mean blood flow velocity but increased cerebral resistance index (+8.1%, p < 0.05) at 4 h and cerebral vasodilatory reserve (+24.8%, p < 0.05). These data suggest that lisinopril produces a paradoxical vasoconstriction of the small cerebral arterioles. This vasoconstriction might be a compensatory mechanism to a dilation of large cerebral arteries, thus resulting in an unchanged cerebral blood flow.
Démolis
P
P
Service de Pharmacologie Clinique, Hôpital de Bicêtre, Le Kremlin-Bicêtre, France.
Carville
C
C
Giudicelli
J F
JF
D000086:Acetazolamide; D000328:Adult; D001783:Blood Flow Velocity / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D002339:Carotid Arteries / Q000187:drug effects* / Q000502:physiology; D002536:Cerebral Arteries / Q000187:drug effects* / Q000502:physiology; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D004311:Double-Blind Method; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D017706:Lisinopril / Q000009:adverse effects / Q000494:pharmacology*; D008297:Male; D012083:Renin / Q000097:blood; D017585:Ultrasonography, Doppler, Transcranial; D014655:Vascular Resistance / Q000187:drug effects; D014661:Vasoconstriction / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects
D017706:Lisinopril; D012083:Renin; D000086:Acetazolamide