Calmodulin-dependent Ca2+ transport in erythrocytes of spontaneously hypertensive rats.

Ca2+ transport in inside-out vesicles of the erythrocyte membranes of spontaneously hypertensive rats (SHR) was studied. In the presence of calmodulin, the rate of 45Ca uptake by the erythrocyte membranes of SHR was half that of erythrocyte membranes of the normotensive control group. It is suggested that the decrease of the rate of calmodulin-dependent calcium transport across the plasma membrane may be a cause for the increased intracellular calcium content found in some tissues of spontaneously hypertensive rats in previous studies.