General anesthetics are used to put patients to sleep before surgical procedures. Many general anesthetics work primarily through a brain protein called the GABAA receptor. Benzodiazepines, another widely prescribed type of sedative, also act through this same receptor. However, benzodiazepines have a wide range of calming effects. Low doses can make you feel sedated and high doses can act as an anesthetic. They're often used to treat anxiety, epilepsy, and insomnia.

The GABAA receptor forms a channel through cell membranes. The molecule in the brain that activates the receptor is called GABA. It causes the channel to open, letting in ions to quiet the brain cells' activity. But how anesthetics and benzodiazepines can have different sedating effects hasn't been clearly understood.

To better understand how these drugs interact with the GABAA receptor, a research team led by Drs. Jeong Joo Kim and Ryan Hibbs from the University of Texas Southwestern Medical Center mapped the receptor's atomic structure while it interacted with three different anesthetic drugs (phenobarbital, etomidate, and propofol) and a commonly used benzodiazepine drug called diazepam. The team also mapped the receptor's interactions with a drug used to treat benzodiazepine overdoses, called flumazenil.