In the chronic phase of two-kidney, one-clip renovascular hypertension, the contralateral kidney of post-Goldblatt hypertensive and post-Goldblatt normotensive rats excretes more vasoconstrictive thromboxane in comparison to controls, whereas excretion of vasodilatory prostaglandin is not elevated. However, increased TXB(2) excretion and the absence of an increase in PGE(2) excretion from the contralateral kidney do not appear to be important for the maintenance of high blood pressure in this model of renovascular hypertension.