alpha granules


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α gran·ules

large, rodlike, or filamentous granules found in several types of cells, especially platelets, where they are the most numerous type of granule; contain secretory proteins, including fibrinogen, fibronectin, fibrospondin, von Willebrand factor (collectively known as adhesive proteins) and other proteins (for example, platelet factor 4, platelet-derived growth factor, coagulation factor V).
References in periodicals archive ?
Since all these growth factors are localized in the alpha granules, the influence of AuNPs on their release is probably connected not only with the inhibition or activation of degranulation but also with more complex interaction between adhesion molecules and receptors [27].
BT and PF4 are platelet-specific chemokines and are stored in the platelet alpha granules and released into the blood once the platelets are activated.4 Based on initial observations, these two molecules seemed to represent promising markers of platelet activation; however, very few studies have demonstrated a clinical benefit associated with these markers in acute coronary syndrome and these studies have had inconclusive results.4 We found comparable levels of BT and PF4 in the HBT and control patients.
RANTES was chosen because it is present in PLT alpha granules in relatively high concentration, and therefore should yield a sensitive assessment of the capability of PLTs to degranulate in response to agonist stimulation.
Ultrastructural ab-normalities in 8-SPD show absent to decreased dense granules.' The alpha storage pool disorder 8-SPD leads to gray platelet syndrome (GPS) with large (mean 13 fL) platelets devoid of alpha granules, giving them a ghostly gray color on the peripheral smear.