Fig. 2.

Schematic of the experimental set up. The tubes or arteries were pressurized using and infusion pump that increased the level in a column of water/saline, increasing the transmural pressure. The pressure was measure using a pressure transducer at the level of the water/saline bath. The piezoelectric elements were attached to the walls of the tube/artery. The data from the crystals was digitized using a computer. The tube/artery was sealed on the bottom end with a suture.