title: Effect of oral ingestion of an extract of the herb Uncaria tomentosa on the biodistribution of sodium pertechnetate in rats.
abstract: The aim of the present study was to determine the effect of the oral ingestion of an extract of the herb Uncaria tomentosa (cat's claw) on the biodistribution of the radiobiocomplex sodium pertechnetate (Na99mTcO4) in rats. The animals (male Wistar rats, 2 months old, 180-220 g), were treated (1 mL) with an U. tomentosa extract (32 mg/mL, N = 5) or 0.9% NaCl solution (control, N = 5) for 7 days. After this period, Na99mTcO4 (3.7 MBq, 0.3 mL) was injected through the ocular plexus and after 10 min the rats were killed, the organs isolated and counted in a well-gamma counter. A significant (P < 0.05) alteration in Na99mTcO4 uptake i) from 0.57 +/- 0.008 to 0.39 +/- 0.06 %ATI/organ (P < 0.05) and from 0.57 +/- 0.17 to 0.39 +/- 0.14 %ATI/g (P < 0.05) was observed in the heart, ii) from 0.07 +/- 0.02 to 0.19 +/- 0.07 %ATI/g in the pancreas, and iii) from 0.07 +/- 0.01 to 0.18 +/- 0.07 %ATI/g (P < 0.05) in muscle after treatment with this extract. Although these results were obtained with animals, caution is advisable in the interpretation of the nuclear medicine examination when the patient is using this herb. This finding is probably an example of drug interaction with a radiopharmaceutical, a fact that could lead to misdiagnosis of the examination in clinical practice with unexpected consequences for the patient.
authors.affiliation: Programa de Pós-Graduação em Ciências Médicas, Universidade Federal Fluminense, Niterói, RJ, Brasil. srfmoreno@hotmail.com
authors.forename: S R F
authors.initials: SR
authors.lastname: Moreno
authors.forename: A L C
authors.initials: AL
authors.lastname: Silva
authors.forename: G
authors.initials: G
authors.lastname: Diré
authors.forename: H
authors.initials: H
authors.lastname: Honeycut
authors.forename: J J
authors.initials: JJ
authors.lastname: Carvalho
authors.forename: A L
authors.initials: AL
authors.lastname: Nascimento
authors.forename: M
authors.initials: M
authors.lastname: Pereira
authors.forename: E K
authors.initials: EK
authors.lastname: Rocha
authors.forename: M
authors.initials: M
authors.lastname: Oliveira-Timóteo
authors.forename: A
authors.initials: A
authors.lastname: Arnobio
authors.forename: B
authors.initials: B
authors.lastname: Olej
authors.forename: M
authors.initials: M
authors.lastname: Bernardo-Filho
authors.forename: L Q A
authors.initials: LQ
authors.lastname: Caldas
mesh_terms: D000818:Animals; D020948:Cat's Claw / Q000737:chemistry*; D008297:Male; D010936:Plant Extracts / Q000494:pharmacology; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics*; D051381:Rats; D017208:Rats, Wistar; D013670:Sodium Pertechnetate Tc 99m / Q000493:pharmacokinetics*; D014018:Tissue Distribution
chemical_list: D010936:Plant Extracts; D019275:Radiopharmaceuticals; D013670:Sodium Pertechnetate Tc 99m