title: Guava extract (Psidium guajava) alters the labelling of blood constituents with technetium-99m.
abstract: Psidium guajava (guava) leaf is a phytotherapic used in folk medicine to treat gastrointestinal and respiratory disturbances and is used as anti-inflammatory medicine. In nuclear medicine, blood constituents (BC) are labelled with technetium-99m ((99m)Tc) and used to image procedures. However, data have demonstrated that synthetic or natural drugs could modify the labelling of BC with (99m)Tc. The aim of this work was to evaluate the effects of aqueous extract of guava leaves on the labelling of BC with (99m)Tc. Blood samples of Wistar rats were incubated with different concentrations of guava extract and labelled with (99m)Tc after the percentage of incorporated radioactivity (%ATI) in BC was determined. The results suggest that aqueous guava extract could present antioxidant action and/or alters the membrane structures involved in ion transport into cells, thus decreasing the radiolabelling of BC with (99m)Tc. The data showed significant (P<0.05) alteration of ATI in BC from blood incubated with guava extract.
authors.affiliation: Department of Biophysics and Biometry, Institute of Biology Roberto Alcantara Gomes, University of Estate of Rio de Janeiro, Rio de Janeiro 20551030, Brazil.
authors.forename: P R C
authors.initials: PR
authors.lastname: Abreu
authors.forename: M C
authors.initials: MC
authors.lastname: Almeida
authors.forename: R M
authors.initials: RM
authors.lastname: Bernardo
authors.forename: L C
authors.initials: LC
authors.lastname: Bernardo
authors.forename: L C
authors.initials: LC
authors.lastname: Brito
authors.forename: E A C
authors.initials: EA
authors.lastname: Garcia
authors.forename: A S
authors.initials: AS
authors.lastname: Fonseca
authors.forename: M
authors.initials: M
authors.lastname: Bernardo-Filho
mesh_terms: D000818:Animals; D001773:Blood Cells / Q000187:drug effects / Q000378:metabolism*; D004347:Drug Interactions; D007553:Isotope Labeling / Q000379:methods; D008297:Male; D010936:Plant Extracts / Q000097:blood / Q000494:pharmacology*; D031647:Psidium; D051381:Rats; D017208:Rats, Wistar; D013670:Sodium Pertechnetate Tc 99m / Q000097:blood*
chemical_list: D010936:Plant Extracts; D013670:Sodium Pertechnetate Tc 99m