Uptake Behavior of Thallium-201 in Hindlimb Muscles of Rats

Abstract

[Purpose] We aimed to examine the uptake and retention behavior of the radioisotope thallium-201(201Tl) in 5 hindlimb muscles, the soleus (Sol), plantaris (Pla), gastrocnemius (Gast), extensor digitorum longus (EDL), and tibialis anterior (TA). [Subjects] Male Wistar rats. [Methods] Three experiments were perfomed: 201Tl uptake and retention as a function of time after intravenous injection; uptake and retention under general anesthesia and in the conscious state; Analysis in hindlimb suspension model rats. [Results] There were significant differences between the uptake rates of Sol and other muscles. The uptake rates of the conscious group muscles were significantly higher than those of the unconscious group; the ratio of Sol/EDL uptake was approximately 2.5 for the conscious animals, although that for unconscious animals was 1.3. In hindlimb-suspended rats, no significant differences between Sol and EDL uptake rates were seem throughout the course of the experiment. [Conclusion] In summary, rat skeletal muscles are very sensitive to uptake and retention of 201Tl and are markedly dependent on time from injection, state of consciousness and on the muscular trophicity. The results of the present study suggest that 201Tl may contribute to physiological evaluation of muscle in rehabilitation science.