Nevalainen T J, Haapamäki M M, Grönroos J M
Department of Pathology, University of Turku and Turku University Hospital, Finland.
Biochim Biophys Acta. 2000 Oct 31;1488(1-2):83-90. doi: 10.1016/s1388-1981(00)00112-8.
Six distinct secretory small molecular weight phospholipases A(2) (PLA(2)) have been cloned and characterized from human tissues. Two of them, pancreatic group IB PLA(2) (PLA(2)-IB) and synovial-type group IIA PLA(2) (PLA(2)-IIA) have been studied as to their association to various inflammatory diseases. PLA(2)-IB is a digestive enzyme synthesized by pancreatic acinar cells. In acute pancreatitis, which is characterized by destruction of pancreatic tissue, PLA(2)-IB is released into the circulation, but its role in pancreatic and other tissue damage is still hypothetical. The concentration of PLA(2)-IIA increases in blood plasma in generalized inflammatory response resulting from infections, chronic inflammatory diseases, acute pancreatitis, trauma and surgical operations. PLA(2)-IIA is synthesized in a number of gland cells and is present in cellular secretions on mucosal surfaces including Paneth cells of intestinal mucosa, prostatic gland cells and seminal plasma, and lacrimal glands and tears. PLA(2)-IIA is expressed in hepatoma-derived cells in vitro and hepatocytes in vivo. PLA(2)-IIA is regarded as an acute phase protein and seems to function as an antibacterial agent especially effective against Gram-positive bacteria. Other putative functions in the inflammatory reaction include hydrolysis of cell membrane phospholipids and release of arachidonic acid for prostanoid synthesis.
已从人体组织中克隆并鉴定出六种不同的分泌型小分子磷脂酶A(2)(PLA(2))。其中两种，即胰腺I B组PLA(2)(PLA(2)-I B)和滑膜型II A组PLA(2)(PLA(2)-II A)，已针对它们与各种炎症性疾病的关联进行了研究。PLA(2)-I B是一种由胰腺腺泡细胞合成的消化酶。在以胰腺组织破坏为特征的急性胰腺炎中，PLA(2)-I B会释放到循环系统中，但其在胰腺及其他组织损伤中的作用仍只是一种假设。在由感染、慢性炎症性疾病、急性胰腺炎、创伤和外科手术引起的全身性炎症反应中，血浆中PLA(2)-II A的浓度会升高。PLA(2)-II A在多种腺细胞中合成，存在于黏膜表面的细胞分泌物中，包括肠黏膜的潘氏细胞、前列腺腺细胞和精浆，以及泪腺和泪液。PLA(2)-II A在体外肝癌衍生细胞和体内肝细胞中均有表达。PLA(2)-II A被视为一种急性期蛋白，似乎起到抗菌剂的作用，尤其对革兰氏阳性菌有效。在炎症反应中的其他假定功能包括水解细胞膜磷脂以及释放花生四烯酸用于前列腺素合成。
