Regional renal blood flow in hypertensive patients.

Renal blood flow measurements in three regions of each kidney were carried out in eighteen hypertensive patients using the radioactive Xenon-133 washout technique in conjunction with renal angiography. It was found that the regional differences were generally small but differences existed in four patients significant in spite of normal angiographic findings. The reduction in blood flow in the two kidneys was generally of the same degree which implies a uniform response to the elevated blood pressure.