Type II diabetics with macrovascular complications: polymorphonuclear leukocyte (PMN) filtration, PMN membrane fluidity and cytosolic Ca2+ content after activation.

We evaluated polymorphonuclear (PMN) filtration parameters, membrane fluidity and cytosolic Ca2+ content in 21 normal subjects and in 18 type II diabetics with macrovascular complications (MVC). Evaluations were carried out at baseline and after in vitro activation prolonged for 5 and 15 min. PMA (4-phorbol 12-myristate 13-acetate) and fMLP (N-formyl-methionyl-leucyl-phenylalanine) were used as stimulating agents. TMA-DPH (1-[4-(trimethylamino)phenyl]-6-phenyl-1,3,5-hexatriene) was used as fluorescent probe for the membrane fluidity tests and Fura 2-AM for the cytosolic Ca2+ content. A significant variation was evident in PMN filtration parameters at 5 and 15 min. No variation was present in PMN membrane fluidity and cytosolic Ca2+ content in normals. In type II diabetics with MVC, we found an increase solely in PMN cytosolic Ca2+ content after PMA activation and an early decrease in PMN membrane fluidity and a late increase in PMN cytosolic Ca2+ content after fMLP activation. After PMA activation alone (at 15 min), PMN filtration distinguishes normals from type II diabetics with MVC. The PMN filtration parameters behave similarly in the two groups, but PMN membrane fluidity and cytosolic Ca2+ content behave differently.