《英文msh詞典》Complement 3a
[主題詞] Complement 3a
[入口詞] C3 a
[入口詞] C3a
[中文釋義] 補(bǔ)體3a
[英文釋義] Smaller fragment formed when C3 convertase splits C3 into C3a and C3b. C3a is a 77-amino acid peptide that includes a carboxy-terminal arginine which is crucial for its biological activities. C3a causes symptoms of immediate hypersensitivity (anaphylaxis) including smooth muscle contraction,mast cell histamine release,and local inflammation. It is considered an anaphylatoxin along with C4a,C5a,and C5a des-arginine.