Chronic renal failure: Leukocyte rheology and polymorphonuclear cytosolic Ca2+ concentration

In a group of subjects with chronic renal failure (CRF), we evaluated the l eukocyte rheological activity, expressed as the filtration rate, the polymo rphonuclear (PMN) membrane fluidify and the PMN cytosolic Ca2+ content. Usi ng the St. George's Filtrometer, we determined the filtration rate of unfra ctionated, mononuclear and PMN leukocytes. Using the fluorescent probe 1.4- (trimethylamino)-phenyl-4-phenylhexatriene (TMA-DPH), we examined the PMN membrane fluidify and, using the Fura 2-AM, the PMN cytosolic Ca2+ content. From the results obtained it is evident that only the initial relative flo w rate of unfractionated leukocytes was significantly reduced in subjects w ith CRF while the filtration parameters of mononuclear and PMN cells did no t distinguish normals from CRF subjects. No variation was evident for the P MN membrane fluidity, while the PMN cytosolic Ca2+ content was significantl y increased in CRF subjects. In these subjects no correlation was found bet ween leukocyte filtration parameters, PMN membrane fluidity, PMN cytosolic Ca2+ content and plasma parameters (blood urea nitrogen and serum creatinin e), reflecting the degree of the CRF In conclusion, in CRF subjects the abn ormality of the leukocyte flow properties was restricted to the initial flo w rate of unfractionated leukocytes, whereas the increase of PMN cytosolic Ca2+ content might be attributed to PMN activation.