Effect of dietary tryptophan on the development of hypertension in the Dahl salt-sensitive rat.

Dahl salt-sensitive rats are inbred on the basis of their tendency to develop hypertension when placed on a high salt diet. The present study investigated the effects of chronic dietary tryptophan (trp) at 50 g/kg food on the development of hypertension in these animals under conditions of both normal and elevated dietary salt. Dietary trp attenuated the development of hypertension in inbred Dahl salt-sensitive (DS/JR) rats and had no effect upon the patterns of development of systolic blood pressures in the normotensive controls, the inbred Dahl salt-resistant (DR/JR) rat and the outbred parental Sprague Dawley (SD) rat. Cardiac hypertrophy, which is associated with Dahl salt-induced hypertension, was blocked by the high trp diet. Further work will be necessary to elucidate the mechanisms by which dietary trp protected against the development of hypertension and cardiac hypertrophy in DS/JR rats.