Measurement of regional cerebral blood flow with antipyrine-14C in awake cats.

Abstract

RmvIctx, MARTIN, JANE JEHLE, LOUIS SOKOLOFF, AND SEYMOUR s. KETY. Measurement of regional cerebral blood flow with antt$yrine-14C in awake cats. J. Appl. Physiol. 27(2): 296-300. 1969.-Antipyrine-14C was utilized for the quantitative measurement of regional cerebral blood flow in cats by means of an autoradiographic technique. The advantages of this technique over a previously described method are the uniformity of the brain-blood partition coefficient for antipyrine, the better resolution of the autoradiograms, the ability to make permanent 14C standards, the ability to obtain adjacent sections for histological studies, and the exposure of the autoradiograms at room temperature rather than a t -70 C. Errors in the determination of the tissue concentration of antipyrine-14C can arise from several sources. Those due to errors in replicate optical density measurements plus variations in section thickness were found to be 5.6%. The standards used introduced only a small error since the standard deviation of replicate standards was no greater than 1.1 %. Regional cerebral blood flow was measured in a series of six awake, unrestrained resting cats The values varied from 0.21 ml/g per min in the cerebral white matter to 1.74 ml/g per min in the inferior colliculus. Arterial Pco2 was 34 f 2.9 mm Hg, Po2 was 102 f 8.4 mm Hg, pH was 7.44 f .01, and hematocrit was 29 f 6.67,.