A technical note for the squeezed-flow perfusion method : sensitive monitoring of vasomotion of medium-sized, isolated blood vessels

We introduce an improved perfusion technique that allows sensitive detection of vasomotion as well as differential estimation of drug action upon luminal or abluminal application. The technique employs a short, isolated segment of medium-sized artery (internal diameter 0.7-4.0mm) that would not generate sufficient resistance by conventional technique. By our method, the constant flow goes through a narrow gap between the intimal surface of the vessel and the outer wall of the blind-end tubing that occupies a large dead-space in the vascular lumen. Due to this narrow clearance, subtle vasomotion can be amplified onto the perfusion pressure, while not much flow-rate is necessary to maintain the baseline perfusion pressure. The method also allows application of drugs either from intimal or adventitial side. This technique should provide powerful means for physiological and pharmacological studies on blood vessels.