Repetitive elastance measurement as a means of recording pharmocological responses in vascular smooth muscles

We describe a method of recording pharmacological responses in isolated arterial segments, based on the direct measurement of vascular wall elastance. The segment outflow is intermittently occluded, and the elastance determined from the subsequent pressure—flow relationship. Since the measurement cycle can be repeated 12 times per minute, rapid pharmacological responses can be studied. The method is capable of demonstrating a sigmoid dose—response relationship to noradrenaline added to the perfusate.