Renal corpuscles

Females fed diets for 12 weeks containing 80 mg Pb/kg ration (as lead acetate) alone or in combination with 8 mg Hg/kg (as methylmercury chloride), or 80 mg Cd/kg ration (as cadmium chloride), ora mixture of Pb, Hg, and Cd Renal corpuscles of ducks fed Pb, Fig, or Cd alone or in two-way combinations had minor ultrastructural changes when compared to controls. The diet containing all three metals caused marked ultrastructural changes in kidney 40... 

O. mykiss 5-80 Juveniles exposed for 28 days had alterations of renal corpuscles and renal tubules at 5, 10, 20, or 40 pg/L exposures necrosis of endothelial cells and renal hematopoietic tissue were prominent at 80 pg/L 17... 

The main filtering units of the kidneys are called nephrons-, about one million nephrons are present in each kidney. Each nephron consists of a renal corpuscle and a unit called a tubule. Blood carrying normal metabolic wastes such as urea and creatine moves through a portion of the corpuscle called the glomerulus, where a filtrate forms that contains water, normal metabolic products, and also waste products the filtrate collects in another unit called Bowman s capsule. Glomerular filtrate then moves into a highly convoluted and multifaceted set of tubes - the tubule - where most useful products (water, vitamins, some minerals, glucose, amino acids) are taken back into the blood, and from which waste products are collected as urine. The relative amounts of water and minerals secreted or returned to the blood are under hormonal control. 

The functional unit of the kidney is the nephron. It is made up of the Malpighian bodies or renal corpuscles (consisting of Bowman s capsules and the glomerulus), the proximal tubule, Henle s loop, and the distal tubule, which passes into a collecting duct. The human kidney contains around one million nephrons. The nephrons form urine in the following three phases. 

The ECM has a very wide variety of functions it establishes mechanical connections between cells it creates structures with special mechanical properties (as in bone, cartilage, tendons, and joints) it creates filters (e. g., in the basal membrane in the renal corpuscles see p.322) it separates cells and tissues from each other (e.g., to allow the Joints to move freely) and it provides pathways to guide migratory cells (important for embryonic development). The chemical composition of the ECM is just as diverse as its functions. 

Q1 The glomerulus is a ball of capillaries which is part of the renal corpuscle the other portion of this structure is Bowman s capsule, which forms the start of the nephron. The wall of Bowman s capsule is composed of a layer of specialized epithelial cells with extensions or foot processes which are in contact with the glomerulus and are called podocytes. The gaps between the foot processes are known as slit pores. These pores allow small molecules to pass through the epithelial layer into the nephron tubules. Below the epithelium is a basement membrane which prevents the passage of large proteins and whole cells into the renal tubules. 

Figure 1 Anatomy of the nephron. RC, renal corpuscle (includes glomerulus and Bowman s capsule) PCT, proximal convoluted tubule PST, proximal straight tubule DLH, descending limb of the loop of Henie ALH, ascending limb of the loop of Henie TALH, thick ascending limb of the loop of Henie MD, macula densa DCT, distal convoluted tubule CT, connecting tubule CD, collecting duct.

The kidneys receive the largest blood flow (22-24% of cardiac output) of any organ, relative to the percentage body weight they constitute (cattle, 0.24% horse 0.36% dog, 0.61%). The functional unit of the kidney is the nephron, which comprises a renal corpuscle (glomerulus and Bowman s capsule), proximal convoluted tubule, descending and ascending limbs of the loop of... 

Tubular cells and renal corpuscles Pleuronectes americanus C219 176... 

In order to arrive at urine, the pollutant or its metabolites should be either filtered through the renal corpuscle or secreted across the tubular epithelium. If the pollutants could be transformed into more polar molecules, their passive reabsoption from the tubule would be retarded and they would be excreted more readily from urine (Vander, 1981). 

The functional unit of the kidney is the nephron (Figure 9.2). A human kidney contains approximately one million nephrons. Each nephron is composed of an initial filtering component, called the renal corpuscle, and a renal tubule specialized for reabsorption and secretion of water, electrolytes, and other solutes. The renal corpuscle consists of a compact tuft of interconnected capillary loops called the glomerulus, and a balloon-like capsule, called Bowman s capsule, into which the glomerulus protrudes. The Bowman s capsule is found in the outer part of the kidney, the cortex. Essentially, the capsule is a sealed, expanded sac at the end of the tubule, the rest of which elongates into a twisted and looped tubule in which urine is formed. 

Renal corpuscle—contains the glomerular capsule, which is vascular and plays a critical role in filtration of the blood... 

Located in the cortex of the kidney, the renal corpuscle is the first section of the kidney and is cmistituted of the glomerulus and the Bowman s capsule. The glomerulus is a capiUaiy network between an afferent and an efferent artery. The blood is filtered through the capillaries into the Bowman s capsule, which empties into the renal proximal tubule. 

Dewey GC, Elias H, Appel KR (1966) Stereology of the renal corpuscles of desert and swamp deermice. Nephron 3 352-365... 

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