Authors : R. F. Silva , T. F. Silva , G. F. Dir? , M. L. Gomes , J. F. de Oliveira , E. A. C. Lima , R. L. Jales , M. T. J. A. Catanho and M. Bernardo Filho
Abstract: Medicinal herbs are widely used for the human beings, however, there are many reports about their undesirable toxicological effects. Preparations from Arnica (Arnica montana) flowers have been used in traditional medicine since a long time for the treatment of inflammatory diseases. Red blood cells (RBC) and plasma proteins labeled with technetium-99m (99mTc) have several clinical applications and it has been reported that some natural products are capable of reducing the efficiency of this radiolabeling. The aim of this work was to assess the effect of an extract of Arnica (infusion) on the labeling of blood elements with 99mTc. In the preparation of the extract it was used 200mg of the leaves of Arnica in 10mL of saline solution (NaCl 0.9%). Samples (0.5mL) of blood from Wistar rats were incubated with 0.1 mL of the extract during 1 hour. After that, the samples were incubated with stannous chloride (SnCl2) and 99mTc. The blood was centrifuged and plasma (P) and RBC were isolated. P and RBC were also precipitated with trichloroacetic acid and soluble (S) and insoluble (I) fraction (F) were determined. The results have shown that the extract has reduced the radiolabeling in IF-P (from 75. 91%?3. 58 to 67.26%?7.44). It was described that some extracts as Fucus vesiculosus, Paullinia cupana, Mentha crispa L and Coffea arabica were able to alter the radiolabeling. In the light of the results obtained we suggest that the referred extract may alter the efficiency of labeling of IF-P due to its capacity (i) to oxidize the stannous ion, (ii) to complex with stannous and pertechnetate ions to form double salts, (iii) to compete by the same binding sites to pertechnetate ion or (iv) by the generations of reactive species of Oxygen with direct action on the labeling process.
R. F. Silva , T. F. Silva , G. F. Dir? , M. L. Gomes , J. F. de Oliveira , E. A. C. Lima , R. L. Jales , M. T. J. A. Catanho and M. Bernardo Filho , 2004. Assessment of the Effect of an Extract of Arnica (Arnica montana) on the Radiolabeling of Sanguineous Elements . Journal of Animal and Veterinary Advances, 3: 356-360.