How important is our kidneys to our overall health?

The kidney plays a dominant role in regulating both the volume and composition of extracellular fluid. They serve to ensure that the body maintains a homeostatic internal environment. They achieve this by excreting the appropriate amount of some types of solutes. Both substances produced are excess substances and are therefore wasted alongside foreign substances.

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When the kidneys fail, some problems occur. First-line treatment for renal dysfunction, dysfunction, or dysfunction, or dialysis and kidney transplantation. However, the latter is only common in advanced (end-stage) renal disease.

Functional kidney anatomy

The average weight of each of the two kidneys in the human body is about 150g. There are two areas found in the cross section of the kidney. These are the outer area called the cortex and the inner area called the medulla. Core taxes are usually reddish brown and are detailed. This is due to the presence of the nephron, the functional unit of the kidney.

The medulla oblongata is composed of pyramid tissue units called the renal pyramids. Between the pyramids is a space called the renal column. Blood vessels pass through the renal column. The papilla of the kidney is the structure at the tip of the pyramid and points to the renal pelvis. On average, each kidney has about eight renal pyramids. Both renal pyramids combined with adjacent cortical areas make up the renal lobes.

The renal pelvis is the area next to another area called the phylum, the concave part of the kidney where blood vessels, nerves, and ureters exit. The renal pelvis itself leads to the ureter outside the kidney. On the outside of the kidney, bifurcations to the two or three extensions of the renal pelvis make up the major calyx and further to the adrenal calyx.

Structure and function of nephrons

Each kidney contains about 1,000,000 nephrons, which are composed of the renal corpuscle and parts called the renal tubules. The renal corpuscle is composed of a network of capillaries called glomeruli and the capsule. The crescent-shaped chamber that surrounds it is called Bowman’s capsule. The renal tubule is a long and complex structure that is divided into three parts.

The first is called the proximal tubule (PCT) and is located in the renal cortex. The second section is called the loop of Henle because it forms a loop that passes through the renal medulla. The third and final section is called the distal tubule (DCT) and is also located in the renal cortex.

The DCT, as the name implies, is the farthest and last part of the nephron, connecting its contents to the ducts that line the pyramids and emptying them. All of these collecting ducts collect the contents from several nephrons and fuse when they reach the papilla.

Overview of renal function

Three processes are involved in the formation of urine. These are glomerular filtration, tubular reabsorption, and tubular secretion. Glomerular filtration involves extrafiltration of plasma into the glomerulus. The filtrate collects in the urinary tract of Bowman’s capsule and flows downstream through the tubular lumen.

In the tubular lumen, activity changes its composition and volume. Tubular reabsorption consists of the transport of substances from the tubules. These substances are returned to the blood in the capillaries that surround the renal tubules. Chemical species that are reabsorbed include important ions, metabolites such as glucose and amino acids, water, and small amounts of waste such as uric acid and urea.

In tubular secretion, some substances are transported to the tubules. The terms reabsorption and secretion refer to the transfer of substances from urine and the subsequent transfer of substances to urine, respectively. Both forms of tubular transport can be active or passive, depending on the substance to be moved and other conditions. Excretion is the net total of filtered – (reabsorption and secretion).

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What is the core function of the kidney? How are these related to health?

The kidney is a complex organ that works in conjunction with several other organs and systems in the body. Therefore, it performs a variety of important functions, including:

• Regulation of the concentration of some ions in plasma.These include Na⁺Ca²⁺Mg²⁺K⁺HCO₃^2-2-2-2- And Cl⁺..
• Ensuring acid / base balance by excreting excess H⁺ In the case of excessive acid and excessive HCO secretion₃^2-2-2-2- Adjustment of momentum in liquid by controlling Na if conditions are too basic⁺ And water secretion
• Regulation of arterial blood pressure by regulating sodium excretion and producing substances such as renin that affect blood pressure.
• Elimination of metabolic waste products. This too:
  • Urea, the most common nitrogen-containing product of protein metabolism
  • Uric acid, a metabolite of purine metabolism
  • Creatinine, the end product of muscle metabolism

• Removal of drugs and foreign and toxic compounds
• Production of selected numbers of hormones, including erythropoietin and 1,25-dihydroxyvitamin D₃..
• Degradation of peptide hormones such as glucagon, insulin and parathyroid hormone
• Synthesis of ammonia involved in acid-base metabolism in the body
• Synthesis of substances that affect renal blood flow and sodium secretion. These substances include derivatives of arachidonic acid such as prostaglandins and thromboxane, and kallikrein, a proteolytic enzyme that produces kinin. Prostaglandins are lipids produced at the site of tissue damage or infection associated with injury or illness. They control inflammation, blood flow, thrombus formation, and several other processes that depend on the site of production. Thromboxane is also a prostaglandin that not only stimulates the formation of blood clots, but also stimulates vasoconstriction to limit the diameter of blood vessels and prevent blood loss.Kinin is a protein in the blood that causes inflammation and affects blood pressure

Overall, the kidneys perform several important functions related to the homeostatic control of the extracellular fluid. They are the critical organ for waste removal and maintenance of appropriate levels of water for osmotic pressure. In the absence of homeostatic balance, muscles, nerves, tissues, and whole systems in the body fail; in individuals experiencing kidney failure, a multitude of problems arise which include high blood pressure, heart disease, anemia, mineral and bone disorders, as well as malnutrition.

References:

• Li PK, Garcia-Garcia G, Lui SF, and others Kidney health for everyone everywhere, from prevention to detection and access to impartial care. Cleanne Flor. 2020; 93 (3): 111-122. Doi: 10.5414 / CNWKD Editorial. PMID: 32017699.
• Ogobuiro I, Tuma F. Physiology, Renal. [Updated 2021 Jul 26].. In: StatPearls [Internet].. Treasure Island (FL): StatPearls Publishing; Available from January 2022: https://www.ncbi.nlm.nih.gov/books/NBK538339/
• Soriano RM, Penfold D, Leslie SW. Anatomy, Abdomen and Pelvis, Kidneys. [Updated 2021 Jul 26].. In: StatPearls [Internet].. Treasure Island (FL): StatPearls Publishing; January 2022-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK482385/

References