Measurement of cerebral inhibitory neuronal receptors with positron emission tomography in relation to neuronal injury.

Eighteen adult cats were intubated and anesthetized with 1.5% isoflurane，plastic ear bars to obtain a reproducible head position. In thirteen cats，MCA was exposed with transorbital approach, was ready to be occluded with a microvascularclip. CBF before and during occlusion of MCA，and that immediately after reperfusion was quantified with i.v. bolus injection of D115 D1Olabeled water (200MBq per cat) and a PET instrument for animal scan, SHR2000 （Hamamatsu photonics, Hamamatsu photonics）FWHM=4mm). Adenosine A1 receptor binding potentialcentral benzodiazepine receptor binding potential and CMRglc was serially quantified with 11c - mpdx(200 mbq),11c -flumazenil (200mbq) 18f - fdg (100mbq) respectively. All PET parameters were presented as theright (ischemic)/left (control) ratio. The data of ischemic cat was compared with that of normalcats (N=5). Degree of ischemic damage was evaluated by histological evaluation and/or by T2 weightedMR image with animal MRI system （Unity）more plus,Varian . 4 cats did not survive the 1st day because of brain edema and were classified as mostsevere ischemic insult. Three cats survived and had the infarction both in cortex and striatum. the其他six had infarcted lesion only in striatum. CBF during occlusion of MCA was significantlyreduced in all 3 ischemic group than in normal group. However，no statistically significant difference was found among the ischemic groups. Right/Left ratio of CBFFDG uptake did not show any statistically significant differenceAdenosine A1 receptor binding potential and benzodiazepine receptor binding最具威胁性的减少在组内与一般的或较正常的或milder insult. Of two receptors examined，reduced binding potential of adenosine A1 receptor was more sensitive to the degree of ischemicinsult. In this study，the degree of decreased binding of adenosine A1 receptor after reperfusion and the degree ofPET imaging of cerebral adenosine receptor with C-11 MPDX can be asuitable in vivo imaging technique to evaluate the function of adenosine and adenosine receptor inrelation to cerebral ischemia. Less

Eighteen adult cats were intubated and anesthetized with 1.5% isoflurane, and were held by plastic ear bars to obtain a reproducible head position. In thirteen cats, right MCA was exposed with transorbital approach and was ready to be occluded with a microvascular clip. CBF before and during occlusion of MCA, and that immediately after reperfusion was quantified with i.v. bolus injection of ィイD115ィエD1O labeled water (200MBq per cat) and a PET instrument for animal scan, SHR2000 (Hamamatsu photonics, FWHM=4mm). Adenosine A1 receptor binding potential, central benzodiazepine receptor binding potential and CMRglc was serially quantified with 11C-MPDX (200MBq), 11C-flumazenil (200MBq) 18F-FDG (100 MBq) respectively. All PET parameters were presented as the right (ischemic)/left (control) ratio. The data of ischemic cat was compared with that of normal cats (N=5). Degree of ischemic damage was evaluated by histological evaluation and/or by T2 weighted MR image with animal MRI system (Unity … More plus, Varian). Four cats did not survive the 1st day because of brain edema and were classified as most severe ischemic insult. Three cats survived and had the infarction both in cortex and striatum. The other six had infarcted lesion only in striatum. CBF during occlusion of MCA was significantly reduced in all 3 ischemic group than in normal group. However, no statistically significant difference was found among the ischemic groups. Right/Left ratio of CBF after reperfusion and that of FDG uptake did not show any statistically significant difference among all groups. Adenosine A1 receptor binding potential and benzodiazepine receptor binding potential were significantly reduced in group with severe ischemic insult than that with normal or milder insult. Of two receptors examined, reduced binding potential of adenosine A1 receptor was more sensitive to the degree of ischemic insult. In this study, the degree of decreased binding of adenosine A1 receptor after reperfusion and the degree of ischemic insult correlated well. PET imaging of cerebral adenosine receptor with C-11 MPDX can be a suitable in vivo imaging technique to evaluate the function of adenosine and adenosine receptor in relation to cerebral ischemia. Less