title: Study of the biodistribution of the amantadine labelled with technetium-99m in Wistar female rats.
abstract: Amantadine (AMA) has been described as dopamine stimulant and norepineprhine release, capable to block the N-methyl-D aspartate (NMDA) glutamatergic and nicotinic receptors, enhancing the sexual behavior of the male rats and inducing hypersexuality in humans. The use of technetium-99m (99mTc) can be justified for its physical and chemical properties. The aim of this study was to label and evaluate the bioavailability of the AMA labelled with 99mTc (99mTc-AMA) in Wistar female rats. The solution of 99mTc-AMA was administered by intraperitoneal way and the animals were sacrificed in CO2 chamber 10 min after the administration of the radiotracer. Various organs were removed, weighted, their radioactivity was determined using an auto-gamma counter and the results were expressed as the percentage of the injected activity per gram of tissue (%ATI/g). In the control group only Na99mTcO4 was administered. The analysis of results shows that the highest uptakes 99mTc-AMA treated group were: ovary (7.11 +/- 1.43), spleen (3.54 +/- 1.05), thyroid (2.67 +/- 0.15), stomach (1.56 +/- 1.10), duodenum (0.87 +/- 0.52), muscular tissue (0.57 +/- 0.06), liver (0.52 +/- 0.25), and at control group: thyroid (16.45 +/- 2.57), ovary (1.28 +/- 0.12), liver (1.10 +/- 0.04), spleen (0.57 +/- 0.07) and muscular tissue (0.26 +/- 0.03). The results obtained suggest that 99mTc-AMA may be used to study the bioavailability of amantadine and evaluate its effect in sexual behavior in female rats.
authors.affiliation: Universidade do Estado do Rio de Janeiro, Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biofisica e Biometria, Laboratorio de Radiofarmícia Experimental, Av. 28 de Setembro, 87, CEP 20551-030, Rio de Janeiro, RJ, Brazil.
authors.forename: M B N
authors.initials: MB
authors.lastname: Oliveira
authors.forename: A S
authors.initials: AS
authors.lastname: Fonseca
authors.forename: M
authors.initials: M
authors.lastname: Bernardo-Filho
authors.forename: R
authors.initials: R
authors.lastname: Santos
mesh_terms: D000547:Amantadine / Q000493:pharmacokinetics* / Q000494:pharmacology; D000818:Animals; D000978:Antiparkinson Agents / Q000493:pharmacokinetics; D000998:Antiviral Agents / Q000493:pharmacokinetics; D001682:Biological Availability; D015259:Dopamine Agents / Q000493:pharmacokinetics; D005260:Female; D008297:Male; D009132:Muscles / Q000378:metabolism; D010053:Ovary / Q000000981:diagnostic imaging / Q000378:metabolism; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics*; D051381:Rats; D017208:Rats, Wistar; D012726:Sexual Behavior, Animal / Q000187:drug effects; D013154:Spleen / Q000378:metabolism; D013667:Technetium / Q000493:pharmacokinetics*; D014018:Tissue Distribution
chemical_list: D000978:Antiparkinson Agents; D000998:Antiviral Agents; D015259:Dopamine Agents; D019275:Radiopharmaceuticals; D013667:Technetium; D000547:Amantadine