Cytosolic calcium and hemorheological patterns during arterial hypertension

Hypertension can be considered as a progressive ischaemic syndrome interest ing micro- and macrovasculature. In hypertensives it is possible to observe a link between an increase in pe ripheral resistance and blood viscosity, and a decrease in red blood cell ( RBC) deformability. It is important to underline the link between the increase of blood viscosi ty, the decrease of RBC deformability and the cytosolic calcium level, whic h is related to the ischaemic syndrome in hypertension. The aim of this study was to evaluate the level of Ca++ and its possible co rrelation with hemorheological patterns during arterial hypertension. Two groups were studied: Group 1 consisted of 18 mild hypertensives (11 mal es and 7 pre-menopausal females, aged 39 +/- 3 years). This group was of me dium risk according to WHO and ISH (1999) with no other pathologies apart f rom peripheral occlusive arterial disease II stage type A. Group 2 was made up of 14 healthy subjects (9 males and 5 females, aged 34 +/- 4 years). Th e intraerythrocytic cytosolic calcium was evaluated using a fluorescent mar ker FURA 2/AM (Calbiochem). The following hemorheological parameters were also assessed using the new L aser assisted Optical Rotational Red Cell Analyzer (LORCA) according to the Hardeman method (1994): RBC deformability - Elongation Index (EI), RBC agg regability - aggregation half time (t(1/2)). The data obtained showed that compared to the control group the hypertensiv es had a significantly higher level of intraerythrocytic cytosolic calcium (p < 0.01), plus a significant decrease in EI and t(1/2) evaluated using LO RCA. We also observed a significant correlation (p < 0.01) between an increase i n Ca++ and a decrease in EI in the hypertensive patients. Moreover our study revealed a significant correlation between the increase in intraerythrocytic Ca++ and the t(1/2) decrease. The evaluation of the hemorheological patterns and cytosolic calcium could explain the impairment in peripheral perfusion and oxygenation in hypertens ive patients and could provide a good model for a better evaluation and tre atment of microvasculature perfusion in subjects with essential and complic ated hypertension.