Cerebral effects of a
single dose of intravenous vinpocetine in chronic stroke patients: a PET
study.
Szakall S, Boros I, Balkay L, Emri M, Fekete I, Kerenyi L,
Lehel S, Marian T, Molnar T, Varga J, Galuska L, Tron L, Bereczki D, Csiba L,
Gulyas B.
PET Centre, Debrecen University
Medical School, Hungary.
J Neuroimaging 1998 Oct;8(4):197-204
ABSTRACT
The effects of vinpocetine (Cavinton)
on the cerebral glucose metabolism of chronic stroke patients are studied with
positron emission tomography. The regional and global cerebral metabolic rates
of glucose (CMRglu) and the kinetic constants related to them are quantified
before and after single-dose intravenous vinpocetine treatment. These
measurements are completed with transcranial Doppler sonography and single
photon emission computed tomography to explore the possible mechanisms
underlying the resulting changes in glucose uptake and metabolism in the
brain. The authors' findings indicate that a single-dose vinpocetine
treatment, although it does not affect significantly the regional or global
metabolic rates of glucose, improves significantly the transport of glucose
(both uptake and release) through the blood-brain barrier in the whole brain,
the entire contralateral hemisphere, and in the brain tissue around the
infarct area of the symptomatic hemisphere. These changes are in accord with
increased blood flow in the entire contralateral hemisphere as well as
decreased blood flow velocity and increased peripheral vessel resistance in
the entire symptomatic hemisphere.