Gastrin Radioimmunoassay

Please contact us directly for more specific information about our Gastrin RIA like method comparisons, publications or experiences from other laboratories. We will provide you with all required support to ensure a smooth continuation of your services to your patients! This assay can be offered as alternative to the discontinued Siemens Gastrin RIA. Radioimmunoassay for the quantitative determination of Gastrin in human serum. Gastrin and the vagal nerves are the main regulators of gastric acid secretion. However other factors than gastrin contribute to the gastric acid secretion. The main site for gastrin production is the antropyloric mucosa of the stomach. A few gastrin producing cells may also be found in the duodenum and pancreas. Gastrin occurs in many different forms in human serum. An amidated C-terminal is essential for the biological activity of the gastrins. Progastrin is cleaved from preprogastrin. It has been shown that progastrin is partially sulphated in the tyrosine residues. The progastrin is enzymatically cleaved to the main circulating forms of biologically active gastrin: gastrin-34 and gastrin-17, which occur in sulphated an non-sulphated forms. Small amount of gastrin-52 (also named component 1), gastrin-14 (mini-gastrin) and even smaller fragments have been detected in serum. Gastrin is one of the best studied gut hormones. It occurs in the circulation in several different forms, among those gastrin-34 and gastrin-17, sulphated and non-sulphated. The determination of gastrin is useful in the diagnosis of gastrin-producing tumours and of achylia with or without pernicious anemia. In all these clinical situations the serum gastrin concentration is high. Treatment with powerful antisecretagogues may cause a rise in the serum gastrin concentration, because of an impaired acid feedback inhibition of gastrin release. Measurement of serum gastrin can thus be used to monitor the treatment with antisecretagogues. Normal level of gastrin in human serum: < 60 pmol/l (fasting level obtained with this procedure). Mean value: 25 pmol/l ± 10 pmol/l (1SD). Range: 11-54 pmol/l. Enzyme immunoassay for the in-vitro diagnostic quantitative determination of homovanillic acid (HVA) in human urine. Historically, colorimetric analysis of HVA utilized the reaction of 1-nitroso-2-naphthol with biogenic amines, then the method was improved by substituting 1-nitroso-2-naphthol-4-sulfonic acid. However, the colorimetric methods are not specific for HVA due to known interference by many compounds. Thin layer chromatography (TLC) on silica gel was another approach to determine HVA. This method is slow and requires special equipment. Using a flame-ionization detector and electron-capture detection, a gas chromatographic (GC) method was also developed, but has not been widely adapted due to the relatively poor sensitivity. Furthermore, gas chromatography-mass spectrometry was also used for quantitating of HVA in both serum and urine . Finally high-performance liquid chromatography (HPLC) methods involving initial separation of the biogenic amines by anion-exchange chromatography and final separation by reverse-phase (C18) chromatography have become most common, and preferred methods. These methods are reasonably rapid (although requires sample pretreatment), have excellent sensitivity and little interference from other endogenous compounds or exogenous drugs and foods. Distributed by IBL International