TY - JOUR

T1 - Laser-Doppler Evaluation of Rat Brain Microcirculation

T2 - Comparison with the [14C]-Iodoantipyrine Method Suggests Discordance during Cerebral Blood Flow Increases

AU - Fabricius, Martin

AU - Lauritzen, Martin

PY - 1996/1/1

Y1 - 1996/1/1

N2 - Laser-Doppler flowmetry (LDF) is very popular for measurements of dynamic changes of cerebral blood flow (CBF). We studied whether changes of CBF measured by LDF correlate with CBF measured by the [14C]iodoantipyrine (IAP) technique in the range relevant for most physiological experiments ( -30- + 130%). LDF was recorded biparietally by two laser-Doppler probes in halothane-anesthetized rats. Absolute CBF was measured in tissue samples of both parietal cortices after [14C]iodoantipyrine was given i.v. CBF of one hemisphere was reduced by an episode of cortical spreading depression (CSD), which markedly reduces the responsiveness of the ipsilateral cortical CBF to vasoactive stimuli for up to 30 min, while CBF regulation of the contralateral cortex remains intact. CBF was measured under normoventilated, hypercapnic, and hypoxic conditions. The relative changes of CBF measured by the LDF technique were independent of the preceding baseline LDF value. Absolute CBFIAP values correlated poorly to the simultaneously recorded arbitrary LDF values (r = 0.44). In contrast, the ratio of CBFIAP values correlated with the ratio of the relative LDF changes between the two hemispheres (p < 0.001). At reduced CBF, no significant difference was found between methods. At increased CBF, however, LDF was greater than CBFIAP, as indicated by a slope of correlation of 1.45 (p < 0.005).

AB - Laser-Doppler flowmetry (LDF) is very popular for measurements of dynamic changes of cerebral blood flow (CBF). We studied whether changes of CBF measured by LDF correlate with CBF measured by the [14C]iodoantipyrine (IAP) technique in the range relevant for most physiological experiments ( -30- + 130%). LDF was recorded biparietally by two laser-Doppler probes in halothane-anesthetized rats. Absolute CBF was measured in tissue samples of both parietal cortices after [14C]iodoantipyrine was given i.v. CBF of one hemisphere was reduced by an episode of cortical spreading depression (CSD), which markedly reduces the responsiveness of the ipsilateral cortical CBF to vasoactive stimuli for up to 30 min, while CBF regulation of the contralateral cortex remains intact. CBF was measured under normoventilated, hypercapnic, and hypoxic conditions. The relative changes of CBF measured by the LDF technique were independent of the preceding baseline LDF value. Absolute CBFIAP values correlated poorly to the simultaneously recorded arbitrary LDF values (r = 0.44). In contrast, the ratio of CBFIAP values correlated with the ratio of the relative LDF changes between the two hemispheres (p < 0.001). At reduced CBF, no significant difference was found between methods. At increased CBF, however, LDF was greater than CBFIAP, as indicated by a slope of correlation of 1.45 (p < 0.005).

KW - Cerebral blood flow

KW - Cortical spreading depression

KW - Hypercapnia

KW - Hypoxia

KW - Iodoantipyrine

KW - Laser-doppler flowmetry

UR - http://www.scopus.com/inward/record.url?scp=0030043728&partnerID=8YFLogxK

U2 - 10.1097/00004647-199601000-00018

DO - 10.1097/00004647-199601000-00018

M3 - Journal article

C2 - 8530548

AN - SCOPUS:0030043728

VL - 16

SP - 156

EP - 161

JO - Journal of Cerebral Blood Flow and Metabolism

JF - Journal of Cerebral Blood Flow and Metabolism

SN - 0271-678X

IS - 1

ER -