AJP - Heart and Circulatory Physiology, Vol 253, Issue 5 1289-H1297, Copyright © 1987 by American Physiological Society
[14C]iodoantipyrine and microsphere blood flow estimates in cat brain
F. J. Schuier, S. C. Jones, T. Fedora and M. Reivich
Department of Neurology, University of Pennsylvania, Philadelphia 19105.
A comparison of local cerebral blood flow estimates with the microsphere
and the 4-[N-methyl-14C]iodoantipyrine ([14C]IAP) techniques has been
performed in cats. Good correlation of [14C]IAP with microsphere flow
estimates in the gray matter was found. In the white matter, however,
[14C]IAP flow estimates were consistently lower than microsphere flow
estimates. Error analysis of both techniques and comparison with previous
studies suggest that peculiarities of white matter arterial vasculature
with preferential microsphere accumulation may lead to this discrepancy.
Microspheres did not interfere with flow as shown by the normal appearance
of subsequent [14C]IAP autoradiograms. The number of microspheres seen on
autoradiograms was used for an estimate of microvessels blocked by spheres
and found to be negligible. The study also demonstrates that [14C]IAP is
not diffusion limited up to the observed flow values of 2 ml.g-1.min-1.
Both techniques might be used together for a combination of their
respective advantages, which are temporal and spatial resolution for
microsphere and [14C]IAP, respectively.
