Measurement of blood supply to murine tumours using in vivo red cell labelling and dynamic scintigraphy

Abstract

Summary Blood pool and flow were studied in transplanted adenocarcinomas on the legs of mice. The animals' red blood cells were labelled in vivo by consecutive injections of a stannous compound and 99mTc-pertechnetate. The distribution of radioactivity was then recorded continuously with a gamma camera. This method allows prolonged and repeated estimations of blood supply to undisturbed tumours in conscious mice.It was found that in small tumours (under 1 ml) circulating blood pool was usually high, often 2 or 3 times that in normal leg tissues. In tumours bigger than 1 ml blood pool per unit volume tended to be lower but was still about 1.5 times the normal tissue level. This relatively large blood volume would seem to be outweighed by a very slow rate of flow. Even in the small tumours blood perfusion was greatly reduced compared to that in the normal leg. The blood pool results here provide no evidence that in tumours larger than 1 ml blood supply decreased progressively with growth.

Evaluation of the Microcirculation in a Sheep Island Pedicle Flap with Laser Doppler Flowmeter And99m-Tc-Labelled Red Blood Cells

“…17 Labelled RBCs have been used to study blood flow and blood volume in a rabbit renal artery stenosis model 19 and in transplanted adenocarcinomas on the legs of mice. 18 Dynamic gamma camera imaging following intradermal Xe-133 injections at different sites has been used to measure skin perfusion in man 30 but objections to this technique include, among others, the possible backflow of the xenon through the injection track, and postinjection reactive hyperemia. Young and Hopewell 31 have used the isotope clearance technique with "m-Tc to study skin blood flow in pig flaps at regular time intervals after surgery.…”