Micronutrients
Chuong Pham-Huy, Bruno Pham Huy in Food and Lifestyle in Health and Disease, 2022
Chloride is primarily excreted by the kidney. Cl− undergoes free glomerular filtration with 99% being reabsorbed and about 180 mmol of Cl− excreted per day (15–16). Most of the reabsorption occurs in the proximal tubule of the kidney, by passive reabsorption, ion conductance or active coupled transport with other ions. Cl− excretion is an important mechanism in the kidney’s adaptation to metabolic acidosis and chronic respiratory acid-base disturbances (15–16). Several preclinical studies showed that Cl− depletion induced stimulation of renin secretion resulting in increased systemic blood pressure. In addition, Cl− concentrations may exert direct effects on smooth muscle cells resulting in vasoconstriction (15–16).
Nephrology, including fluid and electrolytes
Jagdish M. Gupta, John Beveridge in MCQs in Paediatrics, 2020
10.3. Which of the following statements about renal tubular function is/are true?Glucose is reabsorbed in the proximal renal tubule.Most of the sodium reabsorption occurs in the distal renal tubule.Most of the potassium excreted in the urine is derived from secretion by distal renal tubule and the collecting duct.Reabsorption of phosphate is inhibited by parathyroid hormone.Urine acidification is carried out in the distal renal tubule.
Liver Diseases
George Feuer, Felix A. de la Iglesia in Molecular Biochemistry of Human Disease, 2020
Tyrosyluria and tyrosinemia are diseases of abnormal tyrosine metabolism. In tyrosyluria or tyrosinosis elevated amounts of tyrosine and its derivatives, particularly p-hydroxyphenylpyruvic acid, are excreted. If the diet contains large amounts of tyrosine, other tyrosyl metabolites, p-hydroxyphenyllactic and p-hydroxyphenylacetic acid, also occur in the urine. Tyrosyluria is characterized by cirrhosis of the liver, and the patient is dying from liver failure during the first week of life, but some cases have survived for months or years. In these cases, multiple renal tubular defects develop. The renal changes may affect to a greater or lesser extent the reabsorption of water, potassium, and bicarbonate ions, uric acid, glucose, amino acids, phosphate, and even protein. Other tubular functions are inconsistent and show variations.
Circadian rhythms of risk factors and management in atherosclerotic and hypertensive vascular disease: Modern chronobiological perspectives of an ancient disease
Published in Chronobiology International, 2023
Yong-Jian Geng, Michael H. Smolensky, Oliver Sum-Ping, Ramon Hermida, Richard J. Castriotta
The release into circulation of the hormone aldosterone from the adrenal cortex enhances the reabsorption of sodium and water by kidney tubules (Rautureau et al. 2011). Additionally, aldosterone participates in processes that promote vascular inflammation, oxidative stress, fibrosis, endothelial dysfunction and structural remodeling, particularly in the presence of elevated plasma sodium chloride concentration (Park and Schiffrin 2002). In endothelial cells and VSMCs, aldosterone, with the influence of Ang-II, exerts effects via mitogen-activated protein kinase (also termed extracellular signal regulated kinase) and cellular Src kinase (a non-receptor tyrosine kinase), plus it partakes in epidermal growth factor receptor transactivation (Mazak et al. 2004; Min et al. 2007; Nakano et al. 2005). Aldosterone thus increases oxidative stress in VSMCs and negatively impacts endothelial function, most likely through reducing the bioavailability of NO (Nakano et al. 2005), and it induces vascular inflammation in endothelial cells through enhancing expression of intercellular adhesion molecule 1 (ICAM-1) and leukocyte adhesion (Caprio et al. 2008).
Phycocyanin improved alcohol-induced hepatorenal toxicity and behavior impairment in Wistar rats
Published in Drug and Chemical Toxicology, 2022
Boukari Oumayma, Khemissi Wahid, Ghodhbane Soumaya, Tebourbi Olfa, Khemais Ben Rhouma, Sakly Mohsen, Hallegue Dorsaf
The kidney is the main body organ which maintains body fluids homeostasis by reabsorption of electrolytes and minerals, alteration of this process causes impairment in renal functions. It has been shown that increased ROS production during the metabolism process of ethanol, specifically the superoxide generation by activating the NADPH oxidase causes such damage (do Vale et al.2017). Moreover, alcohol can also interfere with the proximal tubular cells function and decreases the Na+/K + ATPase activity which leads to functional disturbances (Das Kumar and Vasudevan 2008). In the present study, EtOH group showed a significant increase in creatinine and urea serum levels in comparison to control group which underlies a nephrotoxicity. These changes have been reversed by phycocyanin co-administration (50 mg/kg). Our data are in line with an earlier study showing that oral administration of phycocyanin (25 mg/kg and 50 mg/kg) for 7 days could ameliorate potassium dichromate-induced renal injury evidenced by a decrease in creatinine and urea nitrogen blood levels (Salama et al.2021).
Blood urea nitrogen/albumin ratio on admission predicts mortality in patients with non ST segment elevation myocardial infarction
Published in Scandinavian Journal of Clinical and Laboratory Investigation, 2022
Sarper Sevdımbas, Salim Satar, Muge Gulen, Selen Acehan, Armagan Acele, Gonca Koksaldı Sahin, Deniz Aka Satar
The kidneys’ stability of urea production and excretion determines the BUN concentration. Urea is reabsorbed with sodium and water in the proximal tubule in a passive process; in the more distal nephron, reabsorption of urea is also closely linked to the reabsorption of water under the influence of the antidiuretic hormone, which in turn is affected by angiotensin-II. A high BUN level may reflect a state of renal hypoperfusion resulting from hypovolemia, renovascular disease, or decreased cardiac output [25]. BUN may also increase due to known correlates of cardiovascular risks that are elevated urea reabsorption under the sympathetic nerve activation and renin-angiotensin-aldosterone systems [26]. Consequently, we can state that BUN levels are likely to increase considering the increased sympathetic activity due to heightened neurohumoral activity in patients with myocardial infarction, renal hypoperfusion due to cardiac output, and the activated renin-angiotensin system. This, in turn, can be interpreted as BUN reflects not only cardiorenal function but also neurohumoral activation.
Related Knowledge Centers
- Gastrointestinal Tract
- Glomerulus
- Nephron
- Peritubular Capillaries
- Sodium
- Tubular Fluid
- Urine
- Circulatory System
- Blood
- Renal Physiology