Self-regulation of glomerular filtration rate and renal blood flow

2021-04-30 10:12 PM

Normal glomerular filtration rate still automatically adjusts (that is, it remains relatively constant) despite significant fluctuations in blood pressure that occur during a person's normal functioning.

The outermost part of the kidney, the renal cortex, receives most of the blood flow in the kidney. The amount of blood flow in the kidney marrow is only about 1-2% of the total amount of kidney blood. Blood flows to the kidney marrow by a special capillary system called a straight vessel.

These vessels reach the marrow parallel to the Henle loop and hook with the Henle loop and return to the shell before empties into the vein. Straight vessels are important in allowing the kidneys to concentrate urine.

Valuable glomerular filtration rates in this control include glomerular hydrostatic pressure and glomerular colloid pressure.

These values ​​are influenced by the sympathetic nervous system, hormones and endocrines, and other feedback controls within the kidney.

Board. Hormones and chemicals affect glomerular filtration rate

The normal intrinsic to kidney feedback mechanism maintain renal blood flow and the glomerular filtration rate is relatively stable, although the arterial blood pressure has changed. These mechanisms are still active in the kidney even though it has been eliminated. body, independent.

This is the self-regulation of glomerular filtration rate and renal blood flow. The main functions of the bloodstream self-regulate to supply oxygen and nutrients at normal levels and to eliminate waste products from metabolism, despite changes in arterial pressure. In the kidneys, normal blood flow is much higher than that required for these functions. The main function of self-regulation in the kidneys is to maintain a relatively constant level of glomerular filtration and to allow control of excretion of water and solutes.

Figure. Renal self-regulation of blood volume through the kidneys and glomerular filtration rate, but lacks the ability to self-regulate urine flow when changing renal artery pressure.

Normal glomerular filtration rate still automatically adjusts (that is, it remains relatively constant) despite significant fluctuations in blood pressure that occur during a person's normal functioning. For example, a decrease in blood pressure to as low as 70-75 mm Hg or an increase to as high as 160-180 mm Hg typically changes the glomerular filtration rate 10 percent lower. In general, renal blood flow is automatically adjusted in parallel with glomerular filtration rate, but glomerular filtration rate is more effective than automatic adjustment under certain conditions.



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