Epinephrine (adrenaline), norepinephrine (noradrenaline) together with dopamine constitute the group of catecholamines, which play an important role as hormones and neurotransmitters. After they have exerted their effects, the catecholamines are broken down via intermediate products (metanephrine, normetanephrine, 3- methoxytyramine respectively) and finally excreted in urine. Diseases which are associated with altered levels of catecholamines include hypertonia,degenerative heart diseases, and catecholamine-producing tumors (pheochromocytoma,neuroblastoma, ganglioneuroma). Of these, pheochromocytoma has the greatest significance. Around 10% of all pheochromocytomas show malignant growth and an unidentified pheochromocytoma poses a serious health risk to the patient. The determination of catecholamines is therefore essential in patients with suspected pheochromocytoma.

Chromogranin A (CgA) is an acid glycoprotein with 439 amino acids that is present in the secretory dense core granules of most neuroendocrine cells. The chromogranin family consists of at least three different water-soluble acidic glycoproteins (CgA, CgB, and secretogranin II, sometimes called Chromogranin C).

Upon stimulation, CgA and other peptide hormones and neuropeptides are released. CgA is also secreted from neuroendocrinederived tumors.

Neuroendocrine tumors (NETs), which originate from neuroendocrine cells, are found widely distributed throughout the body. The most common sites of NET are the lung, stomach, appendix, cecum, duodenum, pancreas, jejunum/ileum, colon and rectum. NET arising from the gastrointestinal tract are collectively known as gastroenteropancreatic neuroendocrine tumors (GEP-NET) and account for approximately 2/3 of incident NET. The annual incidence of NET is estimated as 2 – 5 cases per 100,000 population.

CgA is widely expressed throughout the neuroendocrine system and serves as a general biomarker for a wide variety of neuroendocrine tumors. The determination of Chromogranin A helps in the detection of neuroendocrine tumors and is used to assess the course of cancer treatment.

Histamine is a product of decomposition of histidine caused by the growth of certain bacteria in seafood. Fish containing high levels of histamine has been associated with many examples of poisoning commonly referred to as “scombroid poisoning,” a major health problem for consumers. LDN´s trademark HistaSure™ stands for a group of assays based on ELISA  technology for the quantitative and/or semi-quantitative determination of Histamine in seafood – especially for all different kinds of fish samples.

The corresponding sample preparation protocols are based on simple extractions with water and follow the AOAC Official Method 937.07. On a regular base LDN participates at external quality assessment schemes such as  FAPAS – and to date always with success.

All assays only need a minimal amount of lab experience and equipment

Histamine Food ELISA
Quantitative ELISA; high-sensitive and suitable for any kind of food sample

HistaSure™ ELISA Fast Track
AOAC Approved: Fast quantitative or semi-quantitative ELISA; suitable for any kind of fish sample and screening procedures

Cells derived from neuroendocrine tumours (e.g. pheochromocytoma) are known to produce Catecholamines which are secreted episodically via vesicles into the blood stream.

But beside this a small portion of the Catecholamines is metabolized inside the cells to the corresponding catecholamines metabolites – namely Metanephrine (metabolite of Adrenaline), Normetanephrine (metabolite of Noradrenaline) and 3-Methoxytyramine (metabolite of Dopamine) – and then secreted at low levels continuously into the blood stream.
Recent studies and publications have shown that the combined quantification of plasma free Metanephrine (fMN) and plasma free Normetanephrine (fNMN) are the most accurate biochemical markers for the clinical diagnosis of pheochromocytoma and paragangliomas (PPGL) and allow the follow-up of pheochromocytoma patients.
LDN has developed enzyme immunoassays and isotopic assays for the quantitative determination of fMN and fNMN in human plasma.

Serotonin (5-hydroxytryptamine) belongs to the group of biogenic amines and is an intermediate product of the tryptophan metabolism. It plays an important role as a neurotransmitter in the regulation of different behavioural patterns such as motor activity, aggression, sexuality, appetite, depressions, and sleep.

Serotonin can be found in the intestinal mucosa, in urine, and in blood as well as in the central nervous system (CNS). In blood, it is transported predominantly in the platelets.

Diseases which are associated with altered serotonin concentrations include disorders of the CNS, for example autism, epilepsy, schizophrenia and depression, and carcinoid tumors of the intestine or bronchi.

For the determination of Serotonin in serum and urine LDN offers  an enzyme immunoassay. The assay is intended for in-vitro diagnosis and research applications.