Leukocyte Flow Properties,Polymorphonuclear Membrane Fluidity,and Cytosolic Ca 2+ Content in Subjects with Vascular Atherosclerotic Disease with and Without Noninsulin-Dependent Diabetes Mellitus

Abstract

The aim of this research was the evaluation of white blood cell (WBC) filtration, reflecting WBC flow properties, polymorphonuclear cell membrane fluidity, and cytosolic Ca ²⁺ content in subjects with vascular atherosclerotic disease (VAD) and in VAD subjects with noninsulin-dependent diabetes mellitus (NIDDM), in good hemodynamic balance. The authors examined WBC filtration (unfractionated, mononuclear [MN], polymorphonu clear [PMN] cells), using the St. George Filtrometer and considering, respectively, the initial relative flow rate (IRFR) and the clogging rate (CR); the PMN membrane fluidity, employing the fluorescent probe TMA-DPH and calculating the fluorescence polarization degree; and the PMN cytosolic Ca²⁺ content, adopting the fluorescent probe Fura 2-AM and considering the ratio between the Fura 2-Ca2+ complex and the unchelated Fura 2 fluorescence intensity.

The obtained data showed that only the filtration parameters (IRFR, CR) of unfrac tionated WBCs discriminated normal subjects from VAD groups, whereas the filtration parameters of MN and PMN cells did not demonstrate any distinction. PMN membrane fluidity did not distinguish normal subjects from VAD groups, whereas PMN cytosolic Ca²⁺ content was significantly increased in VAD groups in comparison with normal subjects. No relationship was evident between WBC filtration and plasma metabolic para meters ; the correlations obtained between PMN filtration and other PMN parameters need further investigation.