Use of impedance plethysmography to continually monitor bone marrow blood flow

Methods for measuring bone-blood flow are often time-consuming, tedious, single-point measurements which require sacrifice of the animal. An impedance plethysmographic technique is described which can be used to quantify temporal bone marrow blood flow changes. Results obtained with the impedance technique compare favorably with the data from simultaneously administered microspheres. Injection of sympathomimetic drugs produced measurable responses: isoproterenol caused a significant increase in bone marrow blood flow within 1 min and levarterenol decreased bone marrow blood flow. Data obtained with impedance plethysmography suggest that the technique is feasible for multiple measurements on the same animal and that the technique can be used to study acute or chronic changes in bone marrow blood flow following various experimental treatments.