Abstract
The relationship between calyces and pelvis was studied in vitro throughout the simultaneous recording of electromyograms and pressure changes at the upper and lower major calyx and the renal pelvis.
Low voltage potentials with a constant frequency were recorded at the upper calyx. Pressure changes in the upper calyx were correlated in a one to one manner with the electrical discharge recorded at the upper calyx. On the lower calyx, low voltage action potentials with a constant frequency that differed from the upper calyceal rhythm were recorded at the same time. Pressure changes in the lower calyx were in a one to one fashion with the electrical activity at the lower calyx. These pressure changes of the two major calyces were independent and did not conflict with each other.
The pelvic pressure changes correspond in one to one fashion with the action potentials on the same region and its rhythm differ from those at the both two calyces. Pelvic pressure did not reflect the calyceal contraction. Furthermore, calyceal pressures did not reflect the pelvic peristalsis.
We conclude from those data that there is a sphincter action at the pelvi-calyceal border and it protects the calyx, i. e. pacemaker region, from the renal pelvic back pressure.
