Joachim Rapp

Oscillatory Flow Effects on Rat Aortic Smooth Muscle Cells Joachim Rapp

Diplomarbeit, die am 01.02.1997 erfolgreich an einer Universität in USA eingereicht wurde. Abstract: A cell culture System to mimic the circumferential expansion of the arterial wall was supplemented with a flow control System for model enhancement. The given System imposed uniaxial sinusoidal stretch (1 Hz) with a 10 % elongation to an elastic silicone substrate upon which rat aortic smooth muscle cells were cultured. Occurring fluid motion during a stretch experiment caused oscillating shear stress upon the Gell layer of approximately 0.6 dynes/cm2 (60 x 10-3 N/m2) and was controlled by the newly added oscillatory flow System. Experiments were performed and investigated at 0, 4, and 24 hours. Morphological observations correlated with the results obtained by the initial stretch experiments. A final median angle of orientation of 60° - 70° from the axis of stretch was observed. Both control cultures remained randomly oriented throughout all experiments. Inhibition of cell proliferation alter 4 hours of cyclic stretch, observed by Karen J. Schnetzer could not be confirmed. However, growth related results did correspond to the preceding study in a qualitative manner. Influences of oscillatory flow an SMC growth and morphology were not different to the steady-stretch control. Analysis of results confirmed the assumption made for the earlier culture system, that effects of oscillatory fluid motion occurring during the cyclic stretch experiment could be neglected. Table of Contents: |Acknowledgments|V |List of Figures|IX |List of Tables|XI |List of Symbols|XIII 1.|Introduction|1 2.|Background and Literature Review|3 2.1|Arterial Anatomy|4 2.2|Arterial Physiology|6 2.3|Arterial Mechanics|7 2.3.1|Tensile Stress and Arterial Wall Deformation|7 2.3.2|Shear Stress|8 2.4|Arterial Pathology|10 2.4.1|Atherosclerosis|10 2.4.2|Hypertension|12 2.4.3|Smooth Muscle Cells in Arterial Disease|12 2.5|Cell Culture Models of Arterial Mechanics|13