Catecholamines

1. Catecholamines Analysis Service Catecholamines are a group of biogenic amines primarily synthesized in the adrenal medulla or the cells of the sympathetic nervous system from the amino acid tyrosine through the intermediate product dopamine. Dopamine, adrenaline (epinephrine) and noradrenaline (norepinephrine) are members of this group. In response to the physical and emotional stress, catecholamines are released into the bloodstream and act as important hormones and neurotransmitters. By binding to specific receptors on the membranes of target cells, catecholamines play their roles. They assist in the transmission of nerve impulses in the brain, dilation of pupils and bronchioles and promoting the energy release from glucose and fatty acid. Norepinephrine can also constrict blood vessels, increases blood pressure, heart rate and metabolism. With these effects, catecholamine assists in the organism’s adaption to acute and chronic stress. After completing their roles, catecholamines convert to other inactive compounds. Dopamine coverts homovanillic acid (HVA), norepinephrine degrades into normetanephrine and vanillylmandelic acid (VMA), and epinephrine turns into metanephrine and VMA. All of these catecholamine and their metabolites are excreted from the body through the urine. Generally speaking, catecholamines and their metabolites exist in the body in small amounts and only increase apparently during and shortly after physical and emotional stress. However, rare tumors like pheochromocytomas and paragangliomas boost the generation of huge amounts of catecholamines, which in turn result in persistent or sudden bursts of high blood pressure. The symptoms of these tumors include sweating, nausea, anxiety, severe headaches and heart palpitations. Over time, the excess catecholamines may

2. raise the risk for kidney damage, stroke or heart attack and heart failure. To diagnose and treat these tumors are an important issue because hypertension from these tumors can be cured through surgical removal. Urine and plasma are used as materials for determining catecholamines concentrations to help confirming or ruling out the existence of these tumors. . Catecholamine testing measures the amounts of these compounds in the urine and blood. Urine testing is recommended because it’s more reliable. The stress from having blood drawn can increase catecholamine blood concentration. Therefore, results from urine tests are more reliable than blood tests. Catecholamines and their metabolites are rather low in biological samples. This pose a great challenge to sensitivity and pretreatment of the detection methods. In immunoassays, cross-reactivity and non-specific binding may be a problem because they can lead to false-positive results. Thought HPLC- ECD is popular in the analysis of CA and their metabolites. HPLC-ECD is rather labor consuming and time-consuming because derivatization steps are essential in HPLC-ECD. The coeluting interference and electrode fouling compromise the reliability of HPLC-ECD. Creative Proteomics offers the HPLC-MS platform with excellent specificity and sensitivity. Platform LC-MS Summary Identification & Quantification of Catecholamines and Their Metabolites Sample Requirement Normal Volume: 400uL plasma, 100 mg tissue, (2E7) cells Minimal Volume: 100uL plasma, 50 mg tissue, (5E6) cells Report A detailed technical report will be provided at the end of the whole project, including the experiment procedure, MS instrument parameters. Analytes are reported as uM/ml, while CV's are generally 10%.

3. The name of the analytes, abbreviation, formula, molecular weight and CAS# would also be included in the report.