A family of mammalian G protein-coupled receptors (GPCRs) has been identified, which are distinct from but related to classical biogenic amine receptors. These receptors, including TA1 and TA2, bind and are activated by trace amines such as tyramine and β-PEA. The identification of these receptors supports the role of trace amines as neurotransmitters in vertebrates. Three of the four human receptors are present in the amygdala, suggesting a potential link to affective disorders. The discovery of this family of receptors may lead to the development of novel therapeutics for various conditions. Trace amines, such as tyramine, are found in low levels in mammalian nervous systems and have been referred to as "false transmitters" due to their ability to displace other amines. However, evidence suggests they function independently of classical amine transmitters. The study used degenerate PCR and other techniques to identify these receptors, and their localization was analyzed. The results indicate that trace amines may play a role in mood regulation and psychiatric disorders. The identification of these receptors provides a means to evaluate the physiological roles of trace amines in higher species and their regulation in disease. The study also highlights the potential therapeutic applications of these receptors.A family of mammalian G protein-coupled receptors (GPCRs) has been identified, which are distinct from but related to classical biogenic amine receptors. These receptors, including TA1 and TA2, bind and are activated by trace amines such as tyramine and β-PEA. The identification of these receptors supports the role of trace amines as neurotransmitters in vertebrates. Three of the four human receptors are present in the amygdala, suggesting a potential link to affective disorders. The discovery of this family of receptors may lead to the development of novel therapeutics for various conditions. Trace amines, such as tyramine, are found in low levels in mammalian nervous systems and have been referred to as "false transmitters" due to their ability to displace other amines. However, evidence suggests they function independently of classical amine transmitters. The study used degenerate PCR and other techniques to identify these receptors, and their localization was analyzed. The results indicate that trace amines may play a role in mood regulation and psychiatric disorders. The identification of these receptors provides a means to evaluate the physiological roles of trace amines in higher species and their regulation in disease. The study also highlights the potential therapeutic applications of these receptors.