To determine if altering ADH function results in differences in tissue levels of ethanol, we developed a method to accurately measure the internal ethanol concentration in ethanol-exposed C. elegans, in which we used a known volume of worm tissue and measured ethanol concentration using gas chromatography. The concentrations that we measured reflect the relative lack of permeability of these nematodes to chemicals in their environment; for 500 mM exogenous ethanol, the wild-type internal concentration is in the range of 70-90 mM (Figure 2b). This translates to blood alcohol concentration (BAC) values of 0.32-0.41%, which would cause profound intoxication in a naïve human drinker. The degree of intoxication associated with these concentrations in C. elegans is also profound, on an agar medium worms exposed to 500 mM ethanol move at approximately 20% of their untreated speeds (Davies et al., 2003, 2004 and see Figure 3a) the amplitude of their body bends is significantly reduced (Davies et al., 2003), and their movement becomes severely uncoordinated.
