Zanker B, Rasokat H, Hadding U, Bitter-Suermann D
Agents Actions Suppl. 1982;11:147-57.
C3a and its C-terminal hexapeptide lead to a dose dependent release of biogenic amines and nucleotides stored in platelet's granules. The release reaction can be measured by tritiated serotonin or by ATP, indicated by an ATP specific bioluminescence assay. We tested the capability of C3a to induce aggregation of washed platelets. The recently described phenomenon of low dose, stimulus specific desensitization of platelets to the anaphylatoxic peptides C3a and C5a could be shown by measuring the release reaction as well as the aggregation. Further we could demonstrate the reversibility of the stimulus specific desensitization within 2 to 3 hours. The desensitization was proven to be temperature dependent. The recovery of function was independent of newly synthetized protein and is discussed as the result of receptor-recycling.
C3a及其C末端六肽可导致血小板颗粒中储存的生物胺和核苷酸呈剂量依赖性释放。释放反应可用氚标记的血清素或ATP来测量，ATP特异性生物发光测定法可对此进行指示。我们测试了C3a诱导洗涤后血小板聚集的能力。通过测量释放反应以及聚集情况，可以证明最近描述的低剂量、刺激特异性血小板对过敏毒素肽C3a和C5a脱敏的现象。此外，我们还能证明刺激特异性脱敏在2至3小时内具有可逆性。已证实脱敏与温度有关。功能的恢复与新合成的蛋白质无关，被认为是受体再循环的结果。
