Trace blood supply through the kidney?

Arterial Supply

The kidneys receive their blood supply from the renal arteries, which branch off from the abdominal aorta. The renal arteries enter the kidneys at the hilum, which is a depression on the medial surface of each kidney.

The renal arteries divide into segmental arteries, which supply blood to the different segments of the kidney. The segmental arteries then divide into interlobar arteries, which run between the renal pyramids. The interlobar arteries give off arcuate arteries, which run along the corticomedullary junction. The arcuate arteries give off interlobular arteries, which run through the renal cortex.

The interlobular arteries give off afferent arterioles, which enter the glomeruli. The afferent arterioles are the first vessels of the nephron.

Venous Drainage

The blood leaves the kidneys via the renal veins. The renal veins join the inferior vena cava, which returns blood to the heart.

The renal veins are formed by the union of interlobar veins, which run between the renal pyramids. The interlobar veins receive blood from the arcuate veins, which run along the corticomedullary junction. The arcuate veins receive blood from the interlobular veins, which run through the renal cortex.

The interlobular veins receive blood from the efferent arterioles, which leave the glomeruli. The efferent arterioles are the second vessels of the nephron.

Nephron Blood Supply

The nephrons are the functional units of the kidneys. Each nephron consists of a glomerulus and a renal tubule.

The glomerulus is a small ball of capillaries that is located in the renal cortex. The renal tubule is a long, winding tube that leads from the glomerulus to the renal pelvis.

The blood supply to the nephron is essential for the process of urine formation. The glomerulus filters blood plasma from the afferent arteriole. The renal tubule reabsorbs water and solutes from the filtrate, and secretes waste products into the filtrate. The filtrate is eventually excreted as urine.

Regulation of Renal Blood Flow

The renal blood flow is regulated by a number of mechanisms, including:

* Autoregulation: This is the ability of the kidneys to maintain a constant blood flow despite changes in systemic blood pressure.

* Neural control: The sympathetic nervous system can constrict the renal arteries and reduce renal blood flow.

* Hormonal control: The renin-angiotensin-aldosterone system (RAAS) is a hormonal system that helps to regulate renal blood flow.