Although controversial over this off-label purpose, benzodiazepines may play a role in lowering blood pressure. They work as an agonist of the GABA-a receptors in the brain, thus slowing down neurotransmission and dilating blood vessels. GABA is an abbreviation for gamma-aminobutyric acid. It is an inhibitory neurotransmitter among others (glycine, adenosine, etc.) GABA-a receptors are ion channels that are the primary target for benzodiazepines. When an agonist binds to this receptor site, the protein channel opens, allowing negative chloride ions entering the channel and penetrating the voltage-gated ion site. Thus, giving negative feedback in neurotransmission and easing stress, anxiety and tension in patients that can be associated with elevated blood pressure. In addition to GABA, benzodiazepines inhibit the re-uptake of a nucleoside chemical called Adenosine, which serves as an inhibitory chemical mentioned above. It also serves as a coronary vasodilator, allowing the cardiac muscle to relax and dilating cardiac arteries.