Differences between 201T1 and 43K Tissue Distribution in Rested and Exercised Rats

J. G. Llaurado; Jane A. Madden; G.A. Smith

doi:10.1055/s-0037-1620715

Nuklearmedizin - NuclearMedicine, Table of Contents

Nuklearmedizin 1981; 20(01): 40-45
DOI: 10.1055/s-0037-1620715

Originalarbeiten – Original Articles

Schattauer GmbH

Differences between ²⁰¹T1 and ⁴³K Tissue Distribution in Rested and Exercised Rats

Unterschiede in der ²⁰¹T1 und ⁴³K Gewebsverteilung in ausgeruhten und ermüdeten Ratten

J. G. Llaurado

¹From the Nuclear Medicine and Research Services of Veterans Administration Medical Center, Marquette University and The Medical College of Wisconsin, Milwaukee, Wisc., USA

,

Jane A. Madden

¹From the Nuclear Medicine and Research Services of Veterans Administration Medical Center, Marquette University and The Medical College of Wisconsin, Milwaukee, Wisc., USA

,

G.A. Smith

¹From the Nuclear Medicine and Research Services of Veterans Administration Medical Center, Marquette University and The Medical College of Wisconsin, Milwaukee, Wisc., USA

› Author Affiliations

Abstract

A comparison is made of relative organ-to-plasma uptake of ⁴³K and ²⁰¹T1 in rats at rest and after exercise (two hour swimming). Organs were obtained 0.5 or 3 hrs after radionuclide injection. Thus, there were four groups each for ⁴³K and ²⁰¹T1. For ²⁰¹Tl the triad kidneys-heart-adrenals was very consistent throughout the four experimental situations in showing the highest uptake, whereas for ⁴³K adrenals-heart-liver predominated at 0.5 hrs and thymus-liver at 3 hrs. The ratio ²⁰¹Tl/⁴³K in myocardium was always greater than unity in all four experimental situations. The heart-to-lung and heart-to-liver uptake ratios were lower in all cases for ⁴³K vs. ²⁰¹T1. One of the most important findings was that exercise always determined an increase of these ratios for ²⁰¹T1, but it had an unfavorable effect on the ⁴³K heart/lung ratio and no definite effect on the ⁴³K heart/liver ratio. Our findings are analyzed in the light of previous publications. It is concluded that these two ions have biologically important different characteristics and that excessive and seemingly unjustified emphasis has been made on their physiological similarity.

Es wurde die relative Organ/Plasma Aufnahme von ⁴³K und ²⁰¹T1 bei Ratten nach vorausgegangener Ruhe und nach physikalischer Übung (2stündigem Schwimmen) verglichen. Die Organe wurden 0,5 und 3 Stunden nach einer Radio-nuklid-Injektion untersucht. Es wurden vier Gruppen für ⁴³K und vier für ²⁰¹T1 gebildet. Die Dreiergruppe Niere-Herz-Nebenniere verhielt sich in den vier Versuchen mit ²⁰¹Tl sehr regelmäßig und zeigte durchwegs die höchste Nuklid-Aufnahme. Hingegen überwog bei ⁴³K die Gruppe Nebenniere-Herz-Leber im 0,5-Stunden-Versuch und die Gruppe Thymus-Leber im 3-Stunden-Versuch. Das Verhältnis ²⁰¹Tl/⁴³K in Herzmuskel war in allen vier Versuchen größer als eins. Das Verhältnis Herz-Lunge und Herz-Leber war in allen Versuchen für ⁴³K kleiner als für ²⁰¹T1. Von besonderem Interesse war die Beobachtung, daß körperliche Anstrengung in allen Experimenten die oben angeführten Verhältniszahlen für ²⁰¹Tl vergrößerten, aber das Ergebnis für ⁴³K Herz-Lunge verkleinerten. Im Versuchsergebnis ⁴³K Herz-Leber konnte kein merkbarer Einfluß festgestellt werden. Unsere Ergebnisse wurden mit früheren Publikationen verglichen und der Schluß gezogen, daß die beiden Ionen biologisch wichtige Unterschiede aufweisen und ihre physiologische Ähnlichkeit zu Unrecht herausgestrichen wurde.

Full Text

References

References
1 Britten J. S, Blank M. Thallium activation of the Na⁺-K⁺)-activated ATPase of rabbit kidney. Biochim. biophys. Acta 1968; 159: 160-166.
2 Gewirtz H, O’Keefe D. D, Pohost G. M, Strauss H. W, Mcllduff J. B, Daggett W. M. The effect of ischemia on thallium-201 clearance from the myocardium. Circulation 1978; 58: 215-219.
3 Hille B. The permeability of the sodium channel to metal cations in myelinated nerve. J. gen. Physiol 1972; 59: 637-658.
2a Hosain F, Hosain P, Spencer R. P. Testicular imaging with thallium-201 and comparison with other radionuclides (Abstract). J. nucl. Med 1978; 19: 720-721.
5 Inturrisi E. C. Thallium activation of K⁺-activated phosphatases from beef brain. Biochim. biophys. Acta 1969; 173: 567-569.
6 Kinsey V. E, McLean I. W, Parker J. Studies on the crystalline lens. XVIII. Kinetics of thallium (TI⁺) transport in relation to that of the alkali metal cations. Invest. Ophthalmol 1971; 10: 932-942.
7 Lameijer W, Van Zwieten P. A. Kinetic behaviour of thallium in the rat. Accelerated elimination of thallium owing to treatment with potent diuretic agents. Ann. Toxicol 1977; 37: 265-273.
8 Llaurado J. G, Madden J. A, Meade R. C, Smith G. A. Distribution of thallium-201 injected into rats following stress: imaging, organ to plasma uptake ratios, and myocardial kinetics. J. nucl. Med 1978; 19: 172-177.
9 Llaurado J. G, Madden J. A, Smith G. A, Meade R. C. Organ-to-plasma uptake ratio of TI-201 in rats injected at rest or after strenuous exercise. An attempt to interpret the so-called redistribution of myocardial TI-201. Eur. J. nucl. Med 1980; 5: 217-220.
10 Mackay A, Davies D. L, Horton P. W. Is thallium-201 of use in the measurement of total exchangeable potassium in man? Eur. J. clin. Invest 1978; 8: 261-262.
11 Markov A. K, Smith R. O, Lehan P. H, Galyean III J. R., Rodriquez G, Hellems H. K. Detection of coronary artery disease with rapid serial rescanning with potassium-43 at rest. Am. J. Cardiol 1979; 43: 778-786.
12 Prokop E. K, Strauss H. W, Shaw J, Pitt B, Wagner jr. H. N.. Comparison of regional myocardial perfusion determined by ionic potassium-43 to that determined by microspheres. Circulation 1974; 50: 978-984.
13 Schelbert H. R, Ashburn W. L, Chauncey D. M, Halpern S. E. Comparative myocardial uptake of intravenously administered radionuclides. J. nucl. Med 1974; 15: 1092-1100.
14 Strauss H. W, Harrison K, Lamgan J. K, Lebowitz E, Pitt B. Thallium-201 for myocardial imaging. Relation of thallium-201 to regional myocardial perfusion. Circulation 1975; 51: 641-645.
15 Zaret B. L, Strauss H. W, Martin N. D, Wells jr. H. P., Flamm jr. M. D.. Noninvasive regional myocardial perfusion with radioactive potassium. New Engl. J. Med 1973; 288: 809-812.