A model for the ASH modulatory pathways. The model is discussed in the text, in the Discussion section. The molecules in the ovals are those studied in this paper. Only the main players are depicted. The question marks indicate that only the type of molecule (GPCR) is known, while its precise identity is not. DAG, diacylglycerol; PA, phosphatidic acid. Arrows indicate proven activities or pathways. Stimuli and molecules upstream of the two modulatory pathways: food, dopamine, octopamine, serotonin, DOP-3, OCTR-1 and SER-5 have been identified by Wragg et al. , Harris et al.  and Ezak and Ferkey  as modulators of the response to dilute octanol.