Meeting Abstract

P3-1  Sunday, Jan. 6 15:30 - 17:30  Using circuit theory to model flow and pressure outputs of the circulatory system of the American lobster, Homarus americanus SCHLEIFER, HJ*; ELLERS, O; JOHNSON, AS; Bowdoin College; Bowdoin College; Bowdoin College

Interest in modeling the human circulatory system has driven a significant amount of research on the topic, resulting in well-developed models based in electric circuit theory. This raises the question, however, of whether this model can be applied to morphologically different organisms with pulsatile hearts. Additionally, the circuitry-based model of the human circulatory system has been used extensively in modeling the behavior of isolated parts of the human circulatory system, where very few have tried building a comprehensive model of the entire circulatory system. This project, therefore, has two major objectives: applying the electrical circuitry analogy to the circulatory system of the lobster, and stringing together a model of the entire system, instead of multiple models of isolated parts of the system. Similar to mammalian circulatory systems, lobsters have a circulatory system made up of compliant vessels, suggesting that the Windkessel pump circuitry theory can apply to lobster as well as human vessels. These systems differ, however, in a few fundamental ways: the lobster heart only has one chamber, there are seven vessels leaving the lobster heart instead of the one leaving the human heart, and the lobster has an open circulatory system instead of the closed mammalian circulatory system. These differences suggest that models built around the human circulatory system would need to be modified to model the lobster circulatory system. From initial analysis, in a system of compliant vessels (treated as individual Windkessel units), increasing compliance with distance from the heart produces a pulse-smoothing effect. Pulse smoothing reduces fluctuation in power in the outer vessels. Compliance also appears to affect the filling and emptying of vessels, causing vessels to fill in a staggered fashion.