kidney pelvis

physiology

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Last updated

June 30, 2026

Quick Summary

The renal pelvis is the enlarged, funnel-shaped upper end of the ureter, which is the tube that carries urine from the kidney to the bladder. It is located within the concave side of the kidney, known as the sinus.12

The renal pelvis has cuplike extensions called calyces that collect urine before it flows into the urinary bladder. The walls of the renal pelvis are lined with a mucous membrane and smooth muscle fibers. These muscles contract in waves, called peristaltic movements, to help push urine towards the ureter and bladder.1

Obstructions in the urinary tract can cause urine to back up into the renal pelvis, leading to distension and potential damage to the kidneys.3

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pregnancy
Urinary tract
…of the kidney, called the kidney pelvis, also becomes dilated. With this dilation of the kidney pelvis and the ureters there is also a loss of tonicity or contractility in the pelvis of the kidney and the ureters. This loss of tonicity during pregnancy is similar to that mentioned in…
Read More
…of the kidney, called the kidney pelvis, also becomes dilated. With this dilation of the kidney pelvis and the ureters there is also a loss of tonicity or contractility in the pelvis of the kidney and the ureters. This loss of tonicity during pregnancy is similar to that mentioned in…
Read More