Theobromine, shown below, is an alkaloid found in chocolate that is structurally similar to caffeine and theophylline. When dogs eat chocolate, the heart, central nervous system, and kidneys are affected. Dogs can experience nausea, restlessness, muscle tremors, incontinence and diarrhea and ultimately death due to the toxicity of theobromine.
What is the mechanism by which theobromine toxicity occurs in dogs? Hint: Consider that the effects of caffeine and theophylline are mediated through a cAMP-dependent pathway.
Note: Theobromine is named for the genus of the cacao plant from which is was derived, Theobroma, which accounts for why the structure does not contain any bromine atoms; the above structure is correct.