The aim of the study was to evaluate the polymorphonuclear leukocyte (PMN) membrane fluidity and PMN cytosolic Ca2+ content in several clinical conditions:
diabetes mellitus, vascular atherosclerotic disease (VAD),
chronic renal failure (CRF),
essential hypertension (EH). In 13 subjects with
insulin-dependent diabetes mellitus (
IDDM), in 24 subjects with
non-insulin-dependent diabetes mellitus (
NIDDM), in 42 VAD subjects, in 23 VAD subjects with
NIDDM, in 15 subjects with CRF and in 12 subjects with EH, we determined the PMN membrane fluidity, obtained marking unstimulated PMN cells with
fluorescent probe 1-[4-(trimethylamino)phenyl]-6-phenyl-1,3,5-hexatriene (
TMA-DPH), and considering the fluorescence polarization degree, and the PMN cytosolic Ca2+ content, obtained marking unstimulated PMN cells with the
fluorescent probe Fura2-AM and considering the ratio between the Fura2-Ca2+ complex and the unchelated
Fura 2 fluorescence intensity. From the obtained data it is evident that PMN membrane fluidity does not distinguish normals from
IDDM subjects,
NIDDM subjects, VAD subjects with and without
NIDDM, CRF subjects and hypertensives. PMN cytosolic Ca2+ content, in comparison with normal controls, is significantly increased in VAD subjects (p < 0.01), in VAD subjects with
NIDDM (p < 0.001), in CRF subjects (p < 0.001) and in hypertensives (p < 0.05). No correlation was found between PMN membrane fluidity and PMN cytosolic Ca2+ content. The study of these PMN parameters can be useful in the understanding of the role of leukocytes in the vascular damage that characterizes these clinical conditions.