Erythrocyte molecular shape modifications in the primary hypertension

During the last 15 years an increasing experimental support for the hypothesis of the involvement of the cell membrane alterations in the pathogenesis of the essential hypertension has been evidentiated. Four key factors have been revealed as involved in the generation of sodium-dependent hypertension: 1) genetic or acquired defect in renal sodium excretion; 2) dietary sodium intake; 3) natriuretic hormone as sodium inhibitor; 4) sodium for calcium exchange in smooth muscle and plasma membranes. Taking into account the fact that all of them could be responsible for the cell shape modifications at molecular level and considering also the fact that the membrane defects are present only in the primary forms of hypertension, a comparative study of erythrocyte shape modifications between control and hypertensive human subjects has been performed. The shapes of cells were investigated by an inverted light microscope after their sedimentation on glass cover slips. The computer analysis of images revealed a significant difference (p less than 0.001) between the control and hypertensive subjects as concern the echinocytes/total cells ratios, concluding that a shape modification of erythrocytes is occurring in case of essential hypertension. The high rate of transformation of biconcave disks into echinocytes found in case of hypertension is correlated with ATP pool decreasing that we have previously observed at the same disease. The results are discussed in terms of molecular membrane properties of the mammalian erythrocytes and their structure proteins/lipids organization. A model of cell shape transformation upon ATP pool control is presented for the hypertensive disease.