Papillary collecting duct

Papillary Collecting Duct

The Papillary Collecting Duct is a crucial component of the kidney's urinary system. It is the final part of the nephron, where the urine is collected before it is transported to the renal pelvis.

File:Papillary Collecting Duct.jpg

Illustration of a Papillary Collecting Duct

Structure

The Papillary Collecting Duct is a tube-like structure that extends from the cortical collecting duct to the tip of the renal papilla. It is lined with a simple columnar epithelium, which is primarily responsible for the final concentration of urine.

Function

The primary function of the Papillary Collecting Duct is to transport urine from the cortical collecting duct to the renal pelvis. During this process, the duct reabsorbs water and certain solutes, which helps in maintaining the body's homeostasis. The duct's permeability to water and solutes is regulated by antidiuretic hormone (ADH) and aldosterone, respectively.

Clinical Significance

Abnormalities in the Papillary Collecting Duct can lead to various kidney disorders. For instance, the inability of the duct to respond to ADH can result in diabetes insipidus, a condition characterized by excessive urination and thirst. Similarly, mutations in the genes encoding the proteins involved in the duct's function can cause polycystic kidney disease, a genetic disorder that results in the growth of numerous cysts in the kidneys.

See Also

• Kidney
• Nephron
• Renal Pelvis
• Cortical Collecting Duct
• Homeostasis
• Antidiuretic Hormone
• Aldosterone
• Diabetes Insipidus
• Polycystic Kidney Disease