Two deoxyglucose (DG) derivatives, (α,β)-2-deoxy-2-amino(ethylcarbamate)-D-glucose (ECB-DG) and (α,β)-2-deoxy-2-amino(1,2-dihydroxypropyl)-D-glucose (DHP-DG), were synthesized and radiolabeled successfully with [99mTc(H2O)3(CO)3]+ complex. [99mTc]-ECB-DG and [99mTc]-DHP-DG complexes were prepared (96% and 93% radiochemical purities respectively) by using 46 mCi of Na99mTcO4 in 1 mL saline. Radi...

INTRODUCTION In this study, the influence of physiological determinants on 18F-fluoro-d-glucose ((18)F-FDG) brain uptake was evaluated in a mouse model of Alzheimer disease. MATERIALS AND METHODS TASTPM (Tg) and age-matched C57BL/6 J (WT) mice were fasted for 10 hours, while another group was fasted for 20 hours to evaluate the effect of fasting duration. The effect of repeatedly scanning was...

The human brain releases a small amount of lactate at rest, and even an increase in arterial blood lactate during anesthesia does not provoke a net cerebral lactate uptake. However, during cerebral activation associated with exercise involving a marked increase in plasma lactate, the brain takes up lactate in proportion to the arterial concentration. Cerebral lactate uptake, together with gluco...

Brain uptake of radiolabeled D and L-lactate, D-glucose and nicotine, as measured by the intra-carotid bolus method, was examined over a range of pH of the injected solution. The uptake of L-lactate was highest at pH 6.1, and lowered significantly at pH 7.2, 7.5 and 8.4. In contrast, the uptake of the D-enantiomer was not as dramatically affected. Glucose uptake was not affected by alterations ...

Physiological activation increases glucose uptake locally in the brain. However, it is not known how high intensity exercise affects regional and global brain glucose uptake. The effect of exercise intensity and exercise capacity on brain glucose uptake was directly measured using positron emission tomography (PET) and [18F]fluoro-deoxy-glucose ([18F]FDG). Fourteen healthy, right-handed men wer...

The dispositions of 50 marketed central nervous system (CNS) drugs into the brain have been examined in terms of their rat in situ (P) and in vitro apparent membrane permeability (P(app)) alongside lipophilicity and free fraction in rat brain tissue. The inter-relationship between these parameters highlights that both permeability and brain tissue binding influence the uptake of drugs into the ...

Positron emission tomography (PET) imaging is in common use preoperatively to clinically evaluate patients who present with central nervous system mass lesions. The usefulness of PET is also recognized as a method to detect intracranial tumorous lesions. A number of papers reportthat some inflammatory processes also showed the uptake of Fluorine-18-Fluorodeoxyglucose (FDG) and Carbon-11-Methion...

Above a certain level of cerebral activation the brain increases its uptake of glucose more than that of O(2), i.e., the cerebral metabolic ratio of O(2)/(glucose + 12 lactate) decreases. This study quantified such surplus brain uptake of carbohydrate relative to O(2) in eight healthy males who performed exhaustive exercise. The arterial-venous differences over the brain for O(2), glucose, and ...

No tumor-specific tracer has yet been found for the detection of brain tumors by external scintiscanning. Glucose is a substrate in high demand by almost all tumors, and therefore an investigation was undertaken into the potential value of glucose and its analogs as tracers for brain tumors. The compounds studied were D-)1-3H)glucose, D-(1-14C)glucose, (3H)3-O-methyl-D-glucose and L-(1-14C)gluc...

Anti-human immunodeficiency virus (HIV) drug penetration into the brain and cerebrospinal fluid (CSF) is necessary to tackle HIV within the CNS. This study examines movement of [(3)H]ritonavir across the guinea pig blood-brain and blood-CSF barriers and accumulation within the brain, CSF, and choroid plexus. Ritonavir is a protease inhibitor, used in combination therapy (often as a pharmacoenha...