And he has some evidence: A drug that blocks those specific GABA receptors also blocks the effects of ethanol in rats. If Olsen’s right, this could be the chemical mechanism that has eluded scientists until now.
That’s why at lower doses it mellows you out. Now, GABA is an inhibitory neurotransmitter-i.e., it slows things down-so ethanol, in sparking these same receptors, would have a similar effect.
It is, Olsen says, “a unique ethanol receptor that responds to low concentrations of ethanol, as produced by one glass of wine, in the brain.” In particular, Olsen is looking at a subtype of the receptors that GABA sticks to, one that is exquisitely sensitive to ethanol. Specifically, he’s looking at one called gamma aminobutyric acid, or GABA. Olsen thinks the key is a neurotransmitter, a molecule that neurons use to talk to each other. In that range, he says, the neural mechanisms that respond to alcohol are very specific and present very interesting targets for treatment-of both drunkenness and hangover. He studies the range of blood alcohol concentrations you get from zero to a couple of drinks. Nobody really knows how booze works in the brain, but Richard Olsen, a neuroscientist at UCLA who studies alcohol use, is pretty far along in figuring that out. (I myself now take a couple of ibuprofen before bed after a long night.) That is, if the mechanism of hangover is an inflammatory response-as to a wound or illness-then maybe anti-inflammatories are the way to dispel it. If it’s correct that cytokines are the key to hangovers, then that would suggest a simple and profound approach to treatment. (So those warnings about sweet drinks might have something to them.) Consuming ethanol with glucose turns out to elevate lactate levels, and one study shows that the presence of lactate makes hangovers worse. A more likely culprit is actually high blood sugar. And it’s not-sugar doesn’t help the morning after. But if low blood sugar were the problem, administering glucose and fructose ought to be the solution. Dehydration itself may not cause hangovers, but it does cause glucose levels to drop, and the body compensates by turning to other sources of energy, which can cause hangover-like symptoms. Low blood sugar is another common explanation, and it has some intuitive power behind it. It’s a nice theory-but it turns out that hangover symptoms are at their worst when acetaldehyde levels are low. Some scientists have pointed to acetaldehyde, a demonstrably toxic byproduct of ethanol breakdown in the body. Over the past five years, researchers have revealed that pretty much everything anyone has ever told you about the causes of hangover is wrong. But in dehydrated people with hangovers, levels of electrolytes don’t differ too much from baseline controls-and when they do, they don’t correlate with hangover severity. Plus, if you’re drinking booze, you’re probably not drinking water.
Sure, it makes sense: Alcohol suppresses the antidiuretic hormone vasopressin, which ordinarily keeps you from peeing too much.