Increased sodium content and altered sodium transport in thymocytes of spontaneously hypertensive rats

1. The intracellular sodium content and the sodium efflux rate constant have been determined in vitro in thymocytes derived from the Okamato-Aoki strain of spontaneously hypertensive rats. 2. A strong positive correlation between the systolic blood pressure and the sodium content of thymocytes was observed (r = 0.59, n = 39, P less than 0.001). 3. The rate constant for total sodium efflux was negatively correlated with systolic blood pressure (r = -0.43, n = 45, P less than 0.005) and this was due to a fall in the ouabain-sensitive component of sodium efflux. 4. Sodium efflux, influx and the thymocyte potassium content were not related to the blood pressure.