Objective To investigate the brain glucose metabolism with 18 F?FDG microPET/CT in mouse models of intracerebral hemorrhage (ICH). Methods A total of 12 healthy adult male mice were randomly divided into sham operation group (group A, n=6) and ICH model group (group B, n=6) by simple random sampling method. The animal models were established by injecting collagenase Ⅳ into the caudate nucleus of mice. Thereafter (5.5±0.3) MBq of 18F?FDG was injected into caudal vein at 6 h, 24 h, 48 h and 3 d, 5 d, 8 d, 14 d, respectively, following anesthesia. 18 F?FDG microPET/CT scans were ac?quired 30 min after the trace injection. SUV in the perihematomal brain tissue of ICH was measured and an?alyzed. Two?sample t test was used to compare SUV between groups. Results ( 1) Some mice had mild neurologic deficit after the sham operation in group A, while all mice had a marked neurologic deficit in group B, especially at 24 h after 18 F?FDG injection. ( 2) After 6 h, FDG uptake in perihematomal brain tis?sue decreased(SUV=0.80±0.04), which significantly lower than that in the opposite side(SUV=1.10± 0?04;t=2.69, P<0.05) and decreased to the minimum at 24 h(SUV=0.50±0.05). 18F?FDG uptake in perihematomal brain tissue began to increase at 3 d(SUV=1.20±0.05) and kept increasing during the 14 d observation. Compared with the group A, glucose metabolism in group B was significantly lower at each time point(t=37.67-86.60, all P<0.05). Conclusions 18 F?FDG microPET/CT may dynamically reflect the changes of brain glucose metabolism in ICH mouse models. The FDG uptake in the center of ICH may disap?pear and the volume of hematoma with decreased uptake may shrink during the observation period.

Free radicals are the intermediates of metabolism,widely exist in the human bodies.Under normal circumstances,the free radicals play an important role in the metabolic process on human body,cell signal pathway,gene regulation,induction of cell proliferation and apoptosis,so as to maintain the normal growth and development of human body and to inhibit the growth of bacteria,virus and cancer.However,when organic lesion occurs affected by external factors or when equilibrium of the free radicals is tipped in the human body,the free radicals will respond integratedly with lipids,protein or nucleic acid which may jeopardize the health of human bodies.This paper summarizes the research progress of the free radicals conducted in recent years,in relations to the perspective of the types,origins,test methods of the free radicals and their relationship with human's health.In addition,the possible mechanisms of environmental pollutants (such as polycyclic aromatic hydrocarbons) mediating oxidative stress and free radicals scavenging in the body were also summarized.