Abstract
During the development of exptl. renal hypertension in dogs, renin was detected in the plasma. The renin level reached a maximum about 1 wk. after both renal arteries were constricted and then gradually diminished. A rise in NPN was often, but not necessarily, present when the renin cone, of plasma was increased. With the development of hypertension, the hypertensinogen content of the plasma remained unchanged or increased some what unless the amt. of renin became excessive, in which case the hypertensinogen con. decreased. No significant changes in the hypertensinase content of the plasma were noted.