Development of A Flow Chamber for Studying Cell Behaviour under Pulsatile Flow

Introduction Because of the complexity and sophistication of the in vivo environment, to systematically study the behavior of cellular response to mechanical forces has mainly relied on the use of in vitro preparations. The parallel plate flow chamber is the most common used for applying fluid shear stress to cultured cells. Most studies used parallel plate flow chambers under steady flow, and only a limited number of in vitro studies concerned with the influence of pulsatile flow. Several kinds of flow chamber were developed which can provide pulsatile flow to cells ( Helmilinger et al , 1991; Ruel et al. , 1995 ;Tacobes et al. , 1998).

Development of A Flow Chamber for Studying Cell Behaviour under Pulsatile Flow

Introduction Because of the complexity and sophistication of the in vivo environment, to systematically study the behavior of cellular response to mechanical forces has mainly relied on the use of in vitro preparations. The parallel plate flow chamber is the most common used for applying fluid shear stress to cultured cells. Most studies used parallel plate flow chambers under steady flow, and only a limited number of in vitro studies concerned with the influence of pulsatile flow. Several kinds of flow chamber were developed which can provide pulsatile flow to cells ( Helmilinger et al , 1991; Ruel et al. , 1995 ;Tacobes et al. , 1998).

Development of a Flow Chamber for Studying Cell Behaviour under Pulsatile Flow

Introduction Because of the complexity and sophistication of the in vivo enviromnent, to systematically study the behavior of cellular response to mechanical forces has mainly relied on the use of in vitro preparations. The parallel plate flow chamber is the most common used for applying fluid shear stress to cultured cells. Most studies used parallel plate flow chambers under steady flow, and only a limited number of in vitro studies concerned with the influence of pulsatile flow. Several kinds of flow chamber were developed which can provide pulsatile flow to cells ( Helmilinger et al , 1991; Ruel et al. , 1995 ;Tacobes et al. , 1998). If the flow in flow chamber similar to the in vivo arterial pulsatile flow can be applied to cultured cells, then more useful information may be achieved.

Development of a Flow Chamber for Studying Cell Behaviour under Pulsatile Flow

Introduction Because of the complexity and sophistication of the in vivo enviromnent, to systematically study the behavior of cellular response to mechanical forces has mainly relied on the use of in vitro preparations. The parallel plate flow chamber is the most common used for applying fluid shear stress to cultured cells. Most studies used parallel plate flow chambers under steady flow, and only a limited number of in vitro studies concerned with the influence of pulsatile flow. Several kinds of flow chamber were developed which can provide pulsatile flow to cells ( Helmilinger et al , 1991; Ruel et al. , 1995 ;Tacobes et al. , 1998). If the flow in flow chamber similar to the in vivo arterial pulsatile flow can be applied to cultured cells, then more useful information may be achieved.

Cerebral microcirculatory changes in hypovolemic hypotension we re investigat ed in rats with a cardio-pulmonary bypass (CPB) during pulsatile and non-pulsati le flow. The hypovolemic hypotension was induced by reducing the CPB flow-rate. In the non-pulsatile flow, the cardiac beat was stopped using a fibrilator, whi le in the pulsatile flow the cardiac function was retained. The pial microcircul ation was observed and recorded during CPB, using fluorescence videomicroscopy. The arteriolar diameter and red cell velocity were measured based on the recorde d videoimages. The flow-rate was calculated from the measured diameter and veloc ity data. The present results showed that the flow-rate remained almost constant up to 60 mmHg arterial pressure during pulsatile flow. On the other hand, in n on-pulsatile flow, the flow-rate decreased with a decrease in arterial pressure, indicating the impairment of microvascular autoregulation. It was suggested th at pulsatile flow has an advantage over non-pulsatile flow in a view-point of ce rebral microcirculatory changes in hypovolemic hypotension. Collaborating researchers: Drs. T. Yamakawa, S. Yamaguchi, Y. Ohnishi (National Cardiovascular Center, Osaka,Japan)