title: Regional cerebral blood flow and distribution of [99mTc]ethyl cysteinate dimer in nonhuman primates.
abstract: Increases in regional cerebral blood flow have been described in a variety of cerebral pathologic states, including stroke and seizure disorders. The usefulness of technetium-99m-labeled cysteinate dimer as a marker in the measurement of regional cerebral blood flow was tested in five cynomolgus monkeys. To expand the range of blood flow to beyond the normal limits, 40 mg/kg i.v. of the carbonic anhydrase inhibitor acetazolamide was administered. Regional cerebral blood flow in all five monkeys was measured using radiolabeled microspheres (before and after acetazolamide) and the marker (after acetazolamide) in 60-70 samples from 12 brain regions. Acetazolamide significantly increased the mean +/- SEM regional cerebral blood flow measured using microspheres from 0.56 +/- 0.21 to 1.71 +/- 0.9 ml/min/g (p less than 0.01 for each region). A significant positive correlation was found between regional cerebral blood flow values calculated using microspheres and the marker after normalizing the values to those in the cerebellum (r = 0.773, p less than 0.0001). The mean +/- SEM regional cerebral blood flow determined using the marker in a single monkey (1.21 +/- 0.04 ml/min/g) did not differ significantly from that determined in the same monkey using microspheres (1.13 +/- 0.04 ml/min/g). These data support the potential use of this new brain perfusion imaging agent to assess regional cerebral blood flow over a clinically relevant range of blood flows.
authors.affiliation: E.I. du Pont de Nemours & Co., Medical Products Department, North Billerica, MA 01862.
authors.forename: C
authors.initials: C
authors.lastname: Orlandi
authors.forename: P D
authors.initials: PD
authors.lastname: Crane
authors.forename: S H
authors.initials: SH
authors.lastname: Platts
authors.forename: R C
authors.initials: RC
authors.lastname: Walovitch
mesh_terms: D000086:Acetazolamide / Q000494:pharmacology; D000818:Animals; D001794:Blood Pressure; D001921:Brain / Q000098:blood supply*; D002339:Carotid Arteries / Q000502:physiology; D002560:Cerebrovascular Circulation; D003545:Cysteine / Q000031:analogs & derivatives*; D006339:Heart Rate; D008252:Macaca fascicularis; D008297:Male; D008863:Microspheres; D009928:Organ Specificity; D015609:Organotechnetium Compounds; D012039:Regional Blood Flow / Q000187:drug effects
chemical_list: D015609:Organotechnetium Compounds; C059659:technetium Tc 99m bicisate; D003545:Cysteine; D000086:Acetazolamide