HPLC electrochemical detection of trace amines in human plasma and platelets and expression of mRNA transcripts of trace amine receptors in circulating leukocytes

Trace Amines and Their Receptors

“…Both PEA and TYR have been reported to be released from activated platelets (D'Andrea et al, 2003), an observation that takes on added interest in light of TAAR-mediated chemotactic responses of leukocytes (see IV.B.3.b. Immunomodulatory Effects).…”

International Union of Pharmacology. LXXII. Recommendations for Trace Amine Receptor Nomenclature

“…Further amounts have been detected in pancreatic islets (Regard et al, 2007), circulating leukocytes of healthy subjects (D'Andrea et al, 2003;Nelson et al, 2007), and in normal small intestinal mucosal and endothelial cells (Kidd et al, 2008).…”

“…Exogenous agonists include amphetamine and its derivatives [e.g., S(ϩ)methamphetamine (pEC 50 at rat receptor ϭ 6.1; Reese et al, 2007) and 3,4-methylenedioxymethamphetamine (pEC 50 at rat receptor ϭ (Borowsky et al, 2001;Wolinsky et al, 2007); X. laevis oocytes cotransfected with TA 1 and CFTR (Borowsky et al, 2001); CHO cells expressing TA 1 and promiscuous G␣ 16 (Navarro et al, 2006) Endogenous agonists Tyramine (pEC 50 ϭ 6.4-6.7), ␤-PEA (pEC 50 ϭ 6.2-7.0), (Borowsky et al, 2001;Wainscott et al, 2007;Barak et al, 2008 (Borowsky et al, 2001;Wolinsky et al, 2007) and G␣ 16 (Navarro et al, 2006;Lewin et al, 2008) in vitro Receptor distribution Studies in humans, RT-PCR showed mRNA encoding TA 1 in stomach, amygdala, kidney, lung, small intestine, cerebellum, dorsal root ganglion, hippocampus, hypothalamus, liver, medulla, pancreas, pituitary, reticular formation, prostate, skeletal muscle, spleen (Borowsky et al, 2001), pancreatic islets (Regard et al, 2007), circulating leukocytes (D'Andrea et al, 2003), and intestinal mucosa/endothelium (Kidd et al, 2008); in rats, mRNA found in cardiac ventricles (Chiellini et al, 2007); in mice, in situ hybridization localized mRNA encoding TA 1 to discrete CNS areas, including the mitral cell layer of the olfactory bulb, trigeminal nuclei, cerebellar Purkinje cells, spinal cord, amygdala, hippocampus, monoaminergic nuclei (Borowsky et al, 2001), and dopaminergic neurons of the substantia nigra …”

“…Levels of trace amines have been measured in human plasma and are in the low nanomolar range (for example, see Zhou et al, 2001;D'Andrea et al, 2003). Tyramine and ␤-PEA have pK i values for human TA 1 of 8.1 and 7.5, respectively (Borowsky et al, 2001) with pEC 50 values in the high nanomolar range (6.2-7.0; Table 3).…”

Trace amine-associated receptor 1—Family archetype or iconoclast?

“…In the kingdom Animalia endogenously produced TAs have been detected in all invertebrate and vertebrate species examined to date, including humans (Philips et al, 1978;D'Andrea et al, 2003a;Berry, 2004). As a result of their widespread occurrence in both the plant and animal kingdoms, foodstuffs can contain appreciable amounts of TAs either inherently (e.g.…”