loop of Henle

Examples of loop of Henle in the following topics:

• Kidney Function and Physiology

  • In the loop of Henle, the permeability of the membrane changes.
  • Additionally, the loop of Henle invades the renal medulla, which is naturally high in salt concentration.
  • Because two sides of the loop of Henle perform opposing functions, it acts as a countercurrent multiplier .
  • The vasa recta around the loop of Henle acts as the countercurrent exchanger.
  • The loop of Henle acts as a countercurrent multiplier that uses energy to create concentration gradients.

• Tubular Reabsorption

  • Reabsorption in the nephron may be either a passive or active process, and the specific permeability of the each part of the nephron varies considerably in terms of the amount and type of substance reabsorbed.
  • The mechanisms of reabsorption into the peri-tubular capillaries include:
  • The filtrate osmolarity drops to 1200 mOsm/L as water leaves through the descending loop of Henle, which is impermeable to ions.
  • In the ascending loop of Henle, which is permeable to ions but not water, osmolarity falls to 100–200 mOsm/L.
  • A diagram of the nephron that shows the mechanisms of reabsorption.

• Nephron, Parts, and Histology

  • The nephron of the kidney is involved in the regulation of water and soluble substances in blood.
  • The JGA secretes an enzyme called renin, due to a variety of stimuli, and it is involved in the process of blood volume homeostasis.
  • The loop of Henle is a U-shaped tube that consists of a descending limb and ascending limb.
  • In contrast, the ascending limb of Henle's loop is impermeable to water but highly permeable to ions, which causes a large drop in the osmolarity of fluid passing through the loop, from 1200 mOSM/L to 100 mOSm/L.
  • Loop of Henle, 8.

• Nephron: The Functional Unit of the Kidney

  • The second part is called the loop of Henle, or nephritic loop, because it forms a loop (with descending and ascending limbs) that goes through the renal medulla.
  • As urine travels down the collecting duct system, it passes by the medullary interstitium, which has a high sodium concentration as a result of the loop of Henle's countercurrent multiplier system.
  • The nephron is the functional unit of the kidney.
  • The glomerulus and convoluted tubules of the nephron are located in the cortex of the kidney, while the collecting ducts are located in the pyramids of the kidney's medulla.
  • Explain the role of the nephron as the functional unit of the kidney

• Regulation of Water Intake

  • Water generated from the biochemical metabolism of nutrients provides a significant proportion of the daily water requirements for some arthropods and desert animals, but it provides only a small fraction of a human's necessary intake.
  • When the osmolarity of blood changes (i.e. it is more or less dilute), water diffusion into and out of the osmoreceptor cells changes.
  • The macula densa cells in the walls of the ascending loop of henle of the nephron is another type of osmoreceptor, however it stimulates the juxtaglomerular apparatus (JGA) instead of the hypothalamus.
  • Angiotensin II acts on the hypothalamus to cause the sensation of thirst.
  • It also causes vasoconstriction, and release of aldosterone, which causes increased water reabsorption in a mechanism that is very similar to that of ADH.

• Internal Anatomy of the Kidneys

  • The cortex and medulla make up two of the internal layers of a kidney and are composed of individual filtering units known as nephrons.
  • The renal medulla contains the majority of the length of nephrons, the main functional component of the kidney that filters fluid from blood.
  • The medulla is the inner region of the parenchyma of the kidney.
  • After entering the capsule, the filtered fluid flows along the proximal convoluted tubule to the loop of Henle and then to the distal convoluted tubule and the collecting ducts, which flow into the ureter.
  • Each of the different components of the nephrons are selectively permeable to different molecules, and enable the complex regulation of water and ion concentrations in the body.

• Overview of Urine Formation

  • The remaining 80% of the blood flows through the rest of the body to facilitate tissue perfusion and gas exchange.
  • The fluid passes through the components of the nephron (the proximal/distal convoluted tubules, loop of Henle, the collecting duct) as water and ions are removed as the fluid osmolarity (ion concentration) changes.
  • The end product of all these processes is urine, which is essentially a collection of substances that has not been reabsorbed during glomerular filtration or tubular reabsorbtion.
  • Urine is mainly composed of water that has not been reabsorbed, which is the way in which the body lowers blood volume, by increasing the amount of water that becomes urine instead of becoming reabsorbed.
  • The other main component of urine is urea, a highly soluble molecule composed of ammonia and carbon dioxide, and provides a way for nitrogen (found in ammonia) to be removed from the body.

• Characteristics of Mammals

  • The presence of hair is one of the most obvious traits of a mammal.
  • The lower jaw of mammals consists of only one bone, the dentary.
  • The jaws of other vertebrates are composed of more than one bone.
  • The kidneys of mammals have a portion of the nephron called the loop of Henle or nephritic loop, which allows mammals to produce urine with a high concentration of solutes; higher than that of the blood.
  • Bones of the mammalian inner ear are modified from bones of the jaw and skull.

• The Loop Rule

  • Kirchhoff's loop rule states that the sum of the emf values in any closed loop is equal to the sum of the potential drops in that loop.
  • In other words, the sum of the electromotive force (emf) values in any closed loop is equal to the sum of the potential drops in that loop (which may come from resistors).
  • Another equivalent statement is that the algebraic sum of the products of resistances of conductors (and currents in them) in a closed loop is equal to the total electromotive force available in that loop.
  • Kirchhoff's loop rule is a simplification of Faraday's law of induction, and holds under the assumption that there is no fluctuating magnetic field linking the closed loop.
  • Kirchhoff's loop rule states that the sum of all the voltages around the loop is equal to zero: v1 + v2 + v3 - v4 = 0.

• Torque on a Current Loop: Rectangular and General

  • This principle is commonly used in motors, in which the loop is connected to a shaft that rotates as a result of the torque.
  • In the center is a rectangular wire loop of length l and width w, carrying current I.
  • To understand the torque, we must analyze the forces acting on each segment of the loop.
  • Thus, the general equation for torque on a loop of any shape, of N turns, each of A area, carrying I current and exposed to a magnetic field B is a value that fluctuates as the loop rotates, and can be calculated by:
  • Identify the general quation for the torque on a loop of any shape