Changes in Renal Function During Physical and Mental Effort

Abstract

Aim of the study was to evaluate the renal responses to physical and mental effort in essential hypertension by means of a noninvasive radioisotopic method.

Renal uptake rate of Tc99m-DMSA was evaluated in 10 subjects. Starting from 5 to 15 minutes after dose injection counts over the kidney region were acquired by means of a gamma-camera time-activity curves were obtained for each kidney.

In non-stimufated patients DMSA uptake rate increased regularly; in the remaining cases both isometric exercise and mental effort induced an abrupt reduction of the uptake rate which increased again after the end of the test.

Although the relation of DMSA uptake rate to renal function is not yet fully understood, we tenatively interpret these results as indicating blood flow reductions during these stressful conditlons.

Key Words:

• Physical and mental effort
• renal blood flow
• Tc^99m-DMSA uptake rate