Heparin tissue storage

Mast Cells and Basophils. The chief sites of histamine storage are mast cells in the tissues and basophils in blood. These cells synthesize histamine and store it in secretory granules along with a heparin-protein complex. In response to specific antigens, mast cells or basophils are sensitized. Histamine is then secreted from the storage granules. Besides the histamine stores in mast cells and basophils, there is evidence of non-mast cell histamine in some tissues, particularly gastric and intestinal mucosa (60). 

It is now many years since it was discovered that heparin is a constituent of the mast cell granule. Because it has been found in mast cells, many assume that this cell is the principal site of synthesis of this polysaccharide. However, there is evidence also that fibroblasts not only make hyaluronic acid, but possibly sulfated chondroitin polysaccharides as well. - There is not always a distinct correlation between the numbers of mast cells and the content of heparin of a particular tissue. The mast cell is found only in connective and reticular tissues. There is some evidence that mast cells in culture may synthesize heparin.However, another point of view has been put forward that the fibroblasts may make the polysaccharide and store it for a time and that, when they are full of these storage granules, they are called mast cells. ... 

If the analyte is very volatile (e.g., propane or butane) and a quantitative analysis is required, a blood sample should be collected directly into the headspace vial in which the analysis will be carried out. Many other volatile compounds are relatively stable in blood and other tissues if simple precautions are taken. In the case of blood, the container used for the sample should be glass, preferably with a cap lined with metal foil greater losses may occur if plastic containers are used. The tube should be as full as possible and should only be opened when required for analysis and then only when cold (4°C). If the sample volume is limited, it is advisable to select the container to match the volume of blood so that there is minimal headspace. An anticoagulant [sodium ethylenediaminetetraacetate (EDTA) or lithium heparin] should be used. Specimen storage between - 5 and 4°C is recommended and 1% (w/v)... 

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