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
SN - 0271-678X
VL - 16
SP - 156
EP - 161
JO - Journal of Cerebral Blood Flow and Metabolism
JF - Journal of Cerebral Blood Flow and Metabolism
IS - 1
ER -