Alpha-adrenoceptors are a group of G protein-coupled receptors that respond to the neurotransmitter norepinephrine or epinephrine. These receptors are widely present in the central nervous system, the heart, the smooth muscle, and the blood vessels. A few synonyms for alpha-adrenoceptor include alpha-adrenergic receptor, alpha receptor, adrenergic receptor alpha subtype, and alpha-agonist receptor. These terms all refer to the same type of receptor, which plays a critical role in regulating physiological responses such as increasing heart rate, blood pressure, and blood glucose levels. Knowing the synonyms for alpha-adrenoceptor can help researchers better understand the complex interactions between the body's physiological systems and drugs that target these receptors.