[99mTc-Q3 uptake property at varying coronary flow rates in isolated rabbit heart: comparison between 99mTc-Q3 and 201Tl].
OBJECTIVE
This experiment was designed to explore myocardial 99mTc-Q3 uptake property.


METHODS
20 New Zealand White rabbit heart perfusion models were prepared and the isolated rabbit hearts were perfused by double-radionuclide method at varying coronary flow rates from 0.52 to 3.75 ml/g wet wt/min using developed perfusion liquid with autoblood in comparison with 201Tl in the absence of tracers recirculation.


RESULTS
Mean 99mTc-Q3 peak instantaneous uptake was lower(0.65 +/- 0.077) and more affected by low rates (P < 0.05) than 201Tl peak instantaneous uptake (0.82 +/- 0.07, P < 0.01).


CONCLUSIONS
These data were interpreted to indicate: 1. 99mTc-Q3 is not as well extracted as 201Tl; 2. varying the coronary flow rate has significant effects on the uptake of 99mTc-Q3 and 201Tl; 3. similarly to 201Tl, the coronary blood flow conditions may be overestimated by the myocardial radioactive uptake acquired with low flow perfusion, but the coronary blood flow conditions may be underestimated by the myocardial radioactive uptake acquired with high flow perfusion. Further studies on retention and clearance of 99mTc-Q3 need to be conducted.
Department of Nuclear Medicine, First Affiliated Hospital, WCUMS, Chengdu 610041, China.
C
C
Fan
T
T
Tan
Y
Y
Li
A
A
Kuang
Z
Z
Liang
Y
Y
Chen
D000818:Animals; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D066298:In Vitro Techniques; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D015609:Organotechnetium Compounds / Q000493:pharmacokinetics*; D010720:Phosphines / Q000493:pharmacokinetics*; D011817:Rabbits; D011877:Radionuclide Imaging; D013794:Thallium Radioisotopes / Q000493:pharmacokinetics*
D015609:Organotechnetium Compounds; D010720:Phosphines; D013794:Thallium Radioisotopes; C081212:technetium Tc 99m Q3