Studies on sodium and calcium contents of cardiovascular tissue in experimental hypertension.

Sodium and calcium contents of cardiovascular tissue in spontaneously hypertensive rats (SHR) and DOCA hypertensive rats were investigated. The effect of salt loading on these contents of SHR and control Wistar rats was also investigated. Calcium content increased with the development of hypertension, but not sodium content particularly in salt loading rats and at the sustained stage of DOCA hypertensive rats. These results suggest that calcium rather than sodium is more intimately related to the increase in blood pressure.