An extract of a formula used in the traditional chinese medicine (Buzhong Yi Qi Wan) alters the labeling of blood constituents with technetium-99m

Buzhong Yi Qi Wan (Buzhong) is a medicinal herb widely used in Traditional Chinese Medicine to treat the digestive and circulatory systems. Red blood cell and plasma proteins labeled with technetium-99m (99mTc) are used in nuclear medicine. The aim of this work was to investigate the effects of an aqueous Buzhong extract on the labeling of blood constituents with 99mTc. Heparinized blood (Wistar rats) was incubated in vitro with different Buzhong extract concentrations and 99mTc-labeling was performed. Plasma (P) and blood cells (BC) were separated and soluble (SF-P, SF-BC) and insoluble (IF-P, IF-BC) fractions were isolated. The radioactivity on blood constituents was determined and the percentage of incorporated radioactivity ( percentATI) was calculated. Buzhong extract at the highest concentrations used altered significantly (p<0.05) the percentATI in blood constituents. Substances present in the Buzhong extract could alter the cellular membrane and/or generation of free radicals that have oxidant properties modifying the labeling of blood constituents with 99mTc.

Buzhong Yi Qi Wan (Buzhong) é uma fórmula utilizada na Medicina Tradicional Chinesa para tratamento de distúrbios nos sistemas digestório e circulatório. Constituintes sangüíneos marcados com tecnécio-99m (99mTc) são usados na medicina nuclear. O objetivo deste estudo foi investigar os efeitos do extrato de Buzhong na marcação de constituintes sangüíneos com 99mTc. Amostras de sangue de ratos Wistar foram incubadas com diferentes concentrações do extrato de Buzhong e a marcação de constituintes sangüíneos com 99mTc foi realizado. Plasma e células sangüíneas foram separados, frações solúveis e insolúveis do plasma e das células sangüíneas foram isoladas. A radioatividade nos constituintes sangüíneos foi contada e as porcentagens de radioatividade incorporada ( por centoATI), determinada. Extrato de Buzhong nas maiores concentrações utilizadas altera significativamente (p<0.05) a por centoATI nos constituintes sangüíneos. Substâncias presentes no extrato de Buzhong poderiam alterar a membrana celular e/ou gerar radicais livres, que têm propriedades oxidantes, modificando a marcação dos constituintes sangüíneos com 99mTc.

Effect of oral ingestion of an extract of the herb Uncaria tomentosa on the biodistribution of sodium pertechnetate in rats

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 percent 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 percentATI/organ (P < 0.05) and from 0.57 ± 0.17 to 0.39 ± 0.14 percentATI/g (P < 0.05) was observed in the heart, ii) from 0.07 ± 0.02 to 0.19 ± 0.07 percentATI/g in the pancreas, and iii) from 0.07 ± 0.01 to 0.18 ± 0.07 percentATI/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.

The ingestión of a Nectandra membran cea extract changes the bioavailability of technetium-99m radiobiocomplex in rat organs

The radiobiocomplexes labeled with technetium-99m (Tc-99m) have been widely used in nuclear medicine in single photon emission computed tomography and in basic research. The aim of this study was to assess the influence of a Nectandra membran cea extract on the bioavailability of the sodium pertechnetate (Na99mTc0(4)) radiobiocomplex in rat organs. The animals were treated with a N. membran cea extract (30 mg/ ml), for 6 days. Na99mTc0(4) was injected, the organs were isolated and weighed, and the radioactivity was determined in each organ ( percentATI/organ). The percentATI/organ was divided by the mass of each organ to calculate the percentATI/g. A significant increase of the percentATI/organ of Na99mTc0(4) was observed in muscle and thyroid as well as in the percentATI/g in the heart, kidney and thyroid. These findings could result from the interaction between components of the plant extract and the radiobiocomplex which may influence the uptake Na99mTc0(4) in rat organs. Therefore, precaution is suggested in the interpretation of nuclear medicine results in patients using this herb.