Nephroptosis and kidney function.

We have investigated the influence of renal mobility on both renal blood flow and glomerular filtration, in order to evaluate its role as a potential intermediate cause of hypertension. In 25 untreated patients we compared between recumbent and upright position the relative change in the following five parameters: effective renal plasma flow (ERPF), glomerular filtration rate (GFR), renal mobility, peripheral plasma renin activity (PRA) and blood pressure. We found a positive correlation between the degree of renal mobility and an observed decrease in ERPF. On the other hand, no relation was found between the former and an observed decrease in GFR. The PRA appeared to rise following the decrease of the ERPF. These observations suggest that renal mobility adds to the orthostatic reduction in renal blood flow.