Which Body System's Main Function Is To Filter The Blood And Eliminate Metabolic Waste?

Integrative medicine perspectives

Anika Niambi Al-Shura BSc, MSOM, PhD , in Mechanisms of Action in Disease and Recovery in Integrative Cardiovascular Chinese Medicine, 2021

The eye receives and transforms vitiated claret

Cardiac veins

Vessels that remove metabolic wastes and deoxygenated blood away from the heart and usually practice not collect occlusive material blocking blood menses.

•: The corking cardiac vein: chief tributary of the coronary sinus. Moves claret away from the anterior aspect of the heart and runs with the LAD.
•: The middle cardiac vein: accompanies the posterior interventricular vein. Moves blood from the posterior interventricular septum, the posterior wall of the left and right ventricles.
•: The minor cardiac vein: accompanies the AM. Removes blood from the right ventricle into the right atrium.
•: The left posterior vein: one of the main tributaries of the coronary sinus. Moves blood away from the inferior wall of the left ventricle.
•: The oblique vein: primary tributary of the coronary sinus. Removes blood from the posterior wall of the left atrium.

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GENITOURINARY Arrangement

Byung-Soo Kim , ... Anthony Atala , in Principles of Tissue Engineering (Second Edition), 2000

KIDNEYS

The kidneys remove metabolic wastes from the blood, control fluid remainder by maintaining homeostasis, and provide important regulatory activities by secreting hormones. End-stage renal failure is a devastating condition that involves multiple organs in affected individuals. Numerous pathologies, such every bit diabetes, hypertension, glomerulonephritis, and obstructive uropathy, result in terminate-stage renal illness. Current available therapies include hemodialysis, peritoneal dialysis, and renal transplantation ( Amiel and Atala, 1999). Although dialysis tin prolong survival for many patients with finish-stage renal disease, but renal transplantation can currently restore renal function. Yet, the morbidity associated with renal transplantation, such every bit allograft failure, immunosuppression, or operative complications, is non trivial. Furthermore, renal transplantation is severely limited past a donor shortage.

There has been an effort directed toward the evolution of extracorporeal bioartificial renal units (Cieslinski and Humes, 1994; MacKay et al., 1998). In this approach, the bioartificial kidney consists of two principal units, glomeruli and tubules, which replace two critical renal functions, excretion and reabsorption. In the bioartificial glomerulus unit, hollow fibers with loftier hydraulic permeability facilitate filtration of blood delivered to the lumen of the fibers. The filtrate is then delivered to the lumen of hollow fibers in the bioartificial tubular unit, and epithelial cells on the lumen reabsorb the isoosmotic ultrafiltrate. It has been demonstrated that the combination of a synthetic filtration device and a renal tubule prison cell therapy device in an extracorporeal perfusion circuit replaces filtration, ship, metabolic, and endocrinologic functions of the kidney in a canis familiaris model (Humes et al., 1999). However, the application of these extracorporeal devices may be best reserved for temporary situations rather than a permanent solution.

Augmentation of either isolated or total renal function with kidney prison cell expansion in vitro and subsequent autologous transplantation may be a feasible solution for complete replacement therapy. Our laboratory demonstrated the reconstruction of functional renal units by implanting isolated and cultured renal cells on three-dimensional polymer scaffolds (Atala et al., 1995; Yoo et al., 1996). Renal cells were successfully harvested, expanded in vitro, seeded onto polymer scaffolds, and implanted into host animals in which the cells tin can proliferate and organize into glomeruli and highly organized tubulelike structures (Fig. 46.one). These structures allowed for solute send past the tubular cells across the membrane, resulting in the excretion of high levels of uric acrid and creatinine through a urinelike fluid. Recent successes in harvesting and expanding renal cells in vitro and the development of biologically agile scaffolds may let the creation of three-dimensional performance renal units that can be applied for fractional or, eventually, full replacement of kidney part.

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Case History

William Due north. Washburn , in Annual Reports in Medicinal Chemistry, 2014

2 Renal Recovery of Glucose

In the course of removal of metabolic waste materials, the kidneys of a healthy individual filter ~ 180 k of glucose from ~ 180 L of blood daily. ^8,ix However, as the glomerular filtrate passes through the proximal tubules, virtually all glucose dissolved in the filtrate is recovered past the activeness of SGLT1 and SGLT2 residing in the lumen-facing upmost membranes of the epithelial cell surface. Both transporters couple the ship of glucose with the transport of Na⁺ using the complimentary energy gained from Na⁺ send to compensate for that required for glucose send. ^ten

Equally much equally 90% of glucose recovery is carried out by SGLT2, a low-affinity, high-capacity glucose transporter that is expressed just in the S1 and S2 segments of the proximal tubule. ^11–13 Any glucose not captured by SGLT2 is recovered past SGLT1, a high-affinity, low-capacity glucose transporter expressed in the S3 segment. SGLT1 is also expressed in the small intestine and the center. ¹⁴ The role of SGLT1 in center is not known; however, in the pocket-sized intestine, SGLT1 is responsible for absorption of glucose and galactose. Pursuit of selective SGLT2 inhibitors was supported by the profile of individuals with familial renal glucosuria (excretion of glucose into the urine). Despite defective functional SGLT2 transporters, these individuals are healthy in all aspects except for beingness profoundly glucosuric, spilling equally much as 140 g of glucose daily in their urine. ^{fifteen,sixteen} In dissimilarity, SGLT1 inhibition appears undesirable since individuals with nonfunctional SGLT1 transporters have glucose–galactose malabsorption, which is manifested by severe diarrhea. ¹⁷

Figure 23.ane illustrates renal glucose recovery prior to and afterward SGLT2 inhibition. The rate of glucose filtration increases linearly with glucose concentration in claret. The recovery rate is essentially coincident with the filtration rate; however, the recovery capacity is finite. One time plasma glucose concentrations exceed the transport maximum (T _m), glucosuria increases linearly with blood glucose levels. An SGLT2 inhibitor would reversibly lower the glucose threshold value from ~ 180 to 200 mg/dL to a much lower value depending on the extent of inhibition, thereby providing a noninsulin-dependent mechanism to reduce claret sugar levels. Reduction of glycemic levels by this machinery is dependent on the mass of glucose excreted daily in urine, which will be proportional to the volume of glomerular filtrate, the glucose concentration in the filtrate, and both the extent and duration of inhibition over the 24- h period. The efficacy of an SGLT2 inhibitor will exist decreased for T2DM patients with diminished renal function.

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ROLE OF THE KIDNEYS | Histology of the Kidney

D.B. McMillan , in Encyclopedia of Fish Physiology, 2011

Introduction

Excretion involves the separation and elimination of metabolic waste matter products from the body. Various organs are involved in this process: the lungs, gills, skin, etc. The kidneys and their ducts are the major full-time excretory organs and contain the excretory system.

In addition to the elimination of metabolic wastes, the excretory system functions in the maintenance of a proper water residuum in the body: an equilibrium of h2o, inorganic salts, and other substances in the internal environment of the organism. There is a great divergence in the problems of water balance encountered by marine, freshwater, and terrestrial vertebrates, and it is remarkable that their kidneys are as much alike as they are.

The kidney of all vertebrates consists of knots of blood vessels, either glomeruli or glomera, closely associated with masses of kidney tubules ( Figures 1(a), ane(b), and 2 ). A single tubule, with its associated blood vessels, is a nephron.

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Laboratory evaluation of kidney role

W. Greg Miller , Lesley A. Inker , in Gimmicky Do in Clinical Chemistry (Fourth Edition), 2020

Abstruse

The kidney is an organ that eliminates metabolic waste molecules into the urine and maintains the concentrations of many organic molecules and electrolytes in the blood. The principle biomarkers for glomerular filtration are blood creatinine and cystatin C. These biomarkers are used in equations to gauge glomerular filtration rate (eGFR), which is the best overall indicator of kidney function. Urine albumin and creatinine are reported as the albumin/creatinine ratio (ACR), which indicates kidney harm to either the glomerulus or tubules. Patients at take a chance for chronic kidney disease (CKD), such every bit diabetics, hypertensives, those with cardiovascular disease, and certain ethnic groups should exist screened for CKD using eGFR and urine ACR to identify CKD early enough that intervention can slow or prevent progression to terminate-stage disease. This affiliate reviews the role of urine full protein, biomarkers for acute kidney injury, and analysis of kidney stones.

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ADME in Drug Discovery

J. Vrbanac , R. Slauter , in A Comprehensive Guide to Toxicology in Nonclinical Drug Evolution (Second Edition), 2017

OTC1

For the elimination of environmental toxins and metabolic waste matter products, the trunk is equipped with a range of broad-specificity transporters that are present in the liver, kidney, and intestine. The polyspecific organic cation transporters OCT1, 2, and 3 (SLC22A1–3) mediate the facilitated ship of a variety of structurally diverse organic cations, including many drugs, toxins, and endogenous compounds. OCT1 and OCT2 are found in the basolateral membrane of hepatocytes, enterocytes, and renal proximal tubular cells. OCT3 has more than widespread tissue distribution and is considered to be the major component of the extra-neuronal monoamine transport system (or uptake-2), which is responsible for the peripheral emptying of monoamine neurotransmitters. Studies with knockout mouse models have directly demonstrated that these transporters tin can have a major touch on on the pharmacological beliefs of various substrate organic cations. The recent identification of polymorphic genetic variants of human OCT1 and OCT2 that severely affect ship activeness thus suggests that some of the interpatient differences in response and sensitivity to cationic drugs may be caused past variable activity of these transporters [39,twoscore].

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Gout

Phillip C. Demio MD , in Integrative Medicine (Second Edition), 2007

Metabolism

Urate (uric acrid) is a metabolic waste product of purine metabolism. Purines are nowadays in about one-half of the genetic material (Deoxyribonucleic acid and RNA messenger, transfer, and ribosomal types); in intermediates for energy transfer (adenosine triphosphate [ATP] and guanosine triphosphate [GTP]); and in second messengers (e.g., cyclic adenosine monophosphate [military camp]). Purines also figure in one-carbon metabolism (as in Due south-adenosylmethionine) and in many other biochemical functions. Not surprisingly, metabolic pathways in humans maintain an excess of purines equally a prophylactic factor for their supply. The presence of a positive feed-forward mechanism in the production of purines further enhances their abundance and high turnover, another cistron contributing to high levels of urate product. Furthermore, primates have no uricase (which drives ane of many pathways used past other animals to dispose of uric acid). ⁱⁱⁱ Finally, land animals do not have the continuous supply of water necessary to maintain all trunk urates in aqueous solution. All of these factors result in a tenuous state that ever borders on urate supersaturation in both the serum and the tissues, with an always-present tendency toward crystallization. Also, hyperuricemia is not the sole cause of crystal formation; dehydration and a lack of crystal inhibitors (mostly citrates) are also contributors. ⁴ Urate is produced in significant quantity only in tissues with xanthine oxidase—namely, liver and small bowel—and is excreted mainly (about 75%) via the kidney, the rest existence eliminated by the small bowel. Thus, the minor intestine is unique in its participation in both production and excretion of purines.

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Volume one

South. Lee Adamson, , ... Bridgette M.P. Byrne , in Fetal and Neonatal Physiology (Fourth Edition), 2011

Overview

Oxygen, carbon dioxide, nutrients, metabolic wastes, and hormones are transported past claret flowing between the placenta and the fetal body in the umbilical string. Normal fetal growth and development depend on ever-increasing umbilical blood flow to meet the growing demand for exchange with the maternal circulation. Growth of the placenta with the respective creation of new vascular channels provides an important mechanism for the long-term regulation of umbilical blood menses. ^1,2 Yet, the focus of this affiliate is the vasoactive regulation of umbilical claret flow, which is achieved by numerous mediators that influence vascular resistance in umbilicoplacental apportionment. Umbilical blood period regulation plays a office in maintaining fetal growth and central arterial pressure level, in perfusion-perfusion matching inside the placenta, and in the closure of the umbilical vessels at birth.

The umbilicoplacental apportionment is critically of import for the normal growth and development of the fetus. This interesting vascular bed has many unique features. For case, the umbilical artery and vein are extremely long and muscular, and the resistance of the placental microcirculation is low. This ways that a significant proportion of the total vascular resistance in this circulation resides in the umbilical vessels themselves. Under normal in utero weather condition, the umbilicoplacental circulation appears to be about maximally dilated, nevertheless the umbilical vessels are highly vasoactive and, unlike most large vessels, are capable of constricting so vigorously that the lumen is obliterated (eastward.yard., at birth). The umbilical artery is sensitive to many circulating vasoconstrictors but has the unusual characteristic of being refractory to agile vasorelaxation by the cyclic adenosine monophosphate (army camp) and cyclic guanosine monophosphate (cGMP) pathways. ^three,four Perhaps the absence of active relaxation contributes to the vasospasm of the umbilical vasculature afterward birth. How the umbilical vessels are maintained in a nigh fully relaxed state throughout pregnancy is an interesting unanswered question.

This chapter begins with a brief description of the anatomy of the umbilicoplacental circulation and the sites of claret catamenia regulation in this bed. The important functions of claret flow regulation and the factors involved are then reviewed, after a brief outline of the major experimental methods that take been used to obtain this information. Finally abnormalities in umbilical claret flow regulation in intrauterine growth restriction (IUGR), a common and serious crusade of mortality and morbidity in man pregnancy, are described.

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Integrated Cardiovascular Function

Robert G. Carroll PhD , in Elsevier'due south Integrated Physiology, 2007

REGULATION

The cardiovascular organization acts to evangelize nutrients and to remove metabolic wastes from the tissues. The organization is organized and then that if there is adequate arterial pressure, tissue local command of resistance can friction match blood menses to tissue metabolic demand (run into Chapter 8).

Arterial blood force per unit area is the primary regulated component of the cardiovascular system. The arterial baroreceptor reflex (see Chapter 8) provides astute neural control of arterial pressure level. The renal regulation of trunk fluid book provides long-term control of arterial pressure level (see Affiliate 11). Both vascular and renal regulatory systems are augmented by endocrine control, particularly the renin-angiotensin system and antidiuretic hormone (ADH).

Blood volume is regulated to a bottom degree by an equivalent reflex, the cardiopulmonary volume receptor reflex. Control of blood book is augmented by renal sympathetic nerves and endocrine agents such as atrial natriuretic hormone, urodilatin, and ADH. All these agents modify the renal handling of h2o and Na⁺ and are described in more detail in Chapter eleven.

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RENAL Office, FLUIDS, ELECTROLYTES, AND NUTRITION FROM Nascence TO Adulthood

Terry W. Hensle , Erica H. Lambert , in Pediatric Urology, 2010

RENAL FUNCTION

The kidneys function to excrete water, solutes, and metabolic wastes in order to maintain a homeostatic internal environment despite fluctuations in nutrition and fluid balance. The integrity of cells depends on the osmolality of the extracellular fluid (ECF). This is kept under tight control through osmoreceptors and volume receptors that permit the brain and kidneys to produce hormones and vasoactive substances to regulate salt and water excretion. The kidneys receive xx% of the cardiac output. Each nephron receives the ultrafiltrate of plasma, which passes through the Bowman space into the renal tubule. More than than 99% of the filtered water, sodium, chloride, and bicarbonate is reabsorbed past the renal tubules and returned to the plasma. Failure to reabsorb virtually all the sodium tin can effect in life-threatening hyponatremia and volume depletion.

The rate of germination of the ultrafiltrate is the GFR, which is calculated from cardiac output and renal plasma flow. GFR is an important measure out of renal function. Adding of GFR is required in situations indicative of renal illness, such as abnormal urinary findings, peripheral edema, or hypertension. GFR in newborn term and preterm infants is less than that in adults. ⁵ In the term infant, GFR is approximately 21 mL/min/1.73 k², ascent to 90 mL/min/1.73 m² by ii weeks of historic period. GFR reaches developed levels (120 mL/min/1.73 m^two) by ane½ to 2 years of age. In addition, the concentrating chapters of preterm and full-term infants is well below that of adults. Infants have immature collecting tubules, which exercise not allow for adequate response to antidiuretic hormone (ADH). Consequently, during an episode of water deprivation, an infant tin increase osmolarity to a maximum of but 900 mOsm/kg, whereas an adult can concentrate urine to 1200 mOsm/kg. The newborn excretes very dilute urine. Term infants have a diminished capacity to excrete excess sodium compared to adults. This gene is thought to be a tubular defect. Uniquely, premature infants are termed "salt wasters"; even during sodium restriction, they excrete high amounts of sodium. (See Chapter ii for a more detailed discussion.)

In the clinical setting, GFR tin be estimated by measuring serum creatinine, a metabolic terminate product of normal muscle metabolism. Creatinine is produced at a constant level and therefore is excreted proportionally to the GFR. In children, creatinine excretion is 15 mg/kg/day, and in adults, it is 20 mg/kg/mean solar day. This discrepancy reflects the increase in muscle mass as children age and grow. In addition, males take a college serum creatinine concentration than females because of their increased musculus mass. Creatinine provides a 10% to twenty% overestimate of GFR, because information technology is freely filtered at the glomerulus just as well is secreted into the renal tubules. In patients with abnormal renal function, the caste of overestimation increases, because a larger corporeality of creatinine is being secreted. However, the creatinine clearance ratio tin can be used to monitor renal function in patients with renal failure. Creatinine clearance (C_Cr, expressed in milliliters per minute) is calculated from the post-obit formula:

$C_{Cr} = \frac{U_{Cr} \times Five}{P_{Cr}}$

where U_Cr is the urine creatinine concentration (mg/dL), P_Cr is the plasma concentration (mg/dL), and V is the urine flow rate (mL/min).

A 24-hour urine collection is needed to determine creatinine clearance simply is oft impossible to obtain in the pediatric population. Considering of the limitations of serum creatinine and creatinine clearance, other diagnostic alternatives have been studied to produce a reliable and easy marking for monitoring pediatric GFR. A novel serum marking to measure kidney part is cystatin C. Cystatin C is a cysteine protease inhibitor that is made at a stable rate by well-nigh nucleated cells and can be measured in serum. Cystatin C does not depend on muscle mass, age, or gender, unlike serum creatinine. ⁶ A meta-analysis comprising approximately 4500 subjects found that cystatin C is a more accurate measurement of GFR than serum creatinine. ^vii In 2004, the U.S. Food and Drug Administration canonical cystatin C equally an alternative measure out of renal role. ^eight Farther studies are needed to evaluate the utility of cystatin C in the pediatric population as a replacement for serum creatinine to mensurate GFR.

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