Development of a Behavioral and Imaging Model of Feeding in Planarians


Excess weight is a major risk factor for type-2 diabetes, cardiovascular disease, and other comorbidities. Animal models of feeding provide insight into the problem and provide a means for the discovery and evaluation of pharmacotherapeutic treatment. Mammalian models are the most commonly used, but recently non-mammalian models have been utilized (e.g., C. elegans). Planarians provide an intermediate model. They are the earliest extant animal with a primitive brain-like structure and are a convenient model of mammalian behavioral endpoints and drug-induced effects. The purpose of the present study was to determine if a quantitative measure of presumptive feeding behavior could be visualized using an imaging technique. Colored food pellets were prepared and in some experiments, plasmid-delivered green fluorescent protein was added. Both visible and fluorescence microscopy displayed clear indication of internalization of the red dye and localization to the digestive system. This new methodology establishes a convenient way to study normal physiological feeding behavior as well as modifications induced by drugs or other exogenous substances.

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R. B. Raffa, C. S. Tallarida, S. R. Patel, S. M. Rawls and E. Krynetskiy, "Development of a Behavioral and Imaging Model of Feeding in Planarians," Pharmacology & Pharmacy, Vol. 3 No. 3, 2012, pp. 364-367. doi: 10.4236/pp.2012.33049.

Conflicts of Interest

The authors declare no conflicts of interest.


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