Use of an extracorporeal arterio-venous shunt and capillary tubes for frequent micro-blood sampling in rats.

ABSTRACT

Because of the importance of frequent sampling during kinetic analysis, we have developed a method that permits frequent, reliable, and rapid access to the blood stream in rats. The method comprises the establishment of an extracorporeal arterio-venous shunt between femoral blood vessels. Quantitative samples of whole blood and plasma are obtained with capillary micro hematocrit tubes. The small sample volume permits repetitive analysis without major changes in hematocrit. There is good agreement between these measures and ordinary pipetting techniques. Kinetic analysis showed good resolution with close correspondence between actual measurements and the final curve of best fit. This method could be employed advantageously in small conscious animals, when frequent small samples are required by experimental design.