Intestinal electrolyte transport

Russell, D.A (1986) Mast cells in the regulation of intestinal electrolyte transport. American Journal of Physiology 251, G253—262. 

Cooke, H J, Reddix, R.A., 1994 Neural regulation of intestinal electrolyte transport In Johnson, L.R. (Ed ), Physiology of the gastrointestinal tract. Raven Press, New York, (NY), pp. 2083-2132. 

Pharmacological studies with selective agonists have shown that opioid control of intestinal electrolyte transport is predominantly mediated by delta opioid receptors [58], while the gastrointestinal propulsion is under the control of mu receptors [59,60]. The antidiarrheal effects of NEP inhibitors, such as acetorphan, the prodrug of thiorphan, have been compared to those of an opiate agonist, loperamide, in a model of castor oil-induced diarrhea in rats. When administered peripherally, they produced a delayed onset of diarrhea with no reduction in the gastrointestinal transit [61,62], as is commonly observed with loperamide [63],... 

Field M, Rao MC, and Chang EB (1989) Intestinal electrolyte transport and diarrheal disease. New England Journal of Medicine 321 800-806 819-824. 

Gum arabic. (GA) modifies paracellular water and electrolyte transport in the small intestine. Digestive Diseases and Sciences, Vol. 48, No.4, (April 2003), pp. 755-760, ISSN 0163-2116. 

Jackson, M. J. Tai, C.-Y., Morphological correlates of weak electrolyte transport in the small intestine, in Dinno, M. A. (ed.), Structure and Function in Epithelia and Membrane Biophysics, Alan R. Liss, New York, 1981, pp. 83-96. 

INTESTINE Characterization of a membrane potassium ion conductance in intestinal secretory cells using whole cell patch-clamp and calcium-sensitive dye techniques, 192, 309 isolation of intestinal epithelial cells and evaluation of transport functions, 192, 324 isolation of enterocyte membranes, 192, 341 established intestinal cell lines as model systems for electrolyte transport studies, 192, 354 sodium chloride transport pathways in intestinal membrane vesicles, 192, 389 advantages and limitations of vesicles for the characterization and the kinetic analysis of transport systems, 192, 409 isolation and reconstitution of the sodium-de-pendent glucose transporter, 192, 438 calcium transport by intestinal epithelial cell basolateral membrane, 192, 448 electrical measurements in large intestine (including cecum, colon, rectum), 192, 459... 

Brown DR, Miller RJ. In Handbook of Physiology. Neurohormonal Control of Fluid and Electrolyte Transport in Intestinal Mucosa. Bethesda, MD American Physiological Society, 1991 527-589. 

The safety and efficacy of senna have been reviewed (4). Its rhein-anthrone-induced laxative effects occur through two distinct mechanisms, an increase in intestinal fluid transport, which causes accumulation of fluid intralumm-ally, and an increase in intestinal motihty. Senna can cause mild abdominal complaints, such as cramps or pain. Other adverse effects are discoloration of the urine and hemorrhoidal congestion. Prolonged use and overdose can result in diarrhea, extreme loss of electrolytes, especially potassium, damage to the surface epithelium, and impairment of bowel function by damage to autonomic nerves. Abuse of senna has also been associated with melanosis coli, but resolution occurs 8-11 months after withdrawal. Tolerance and genotoxicity do not seem to be problems associated with senna, especially when used periodically in therapeutic doses. 

C Calcium and iron supplementation are common causes of constipation. Polycarbophil, a bulk-forming laxative, exerts its therapeutic effect by increasing the mass and water content of stool and by speeding transit time in the colon. Cascara sagrada and sennosides are cathartics, which speed colonic transit time and alter water and electrolyte transport across the colonic mucosa. Sodium biphosphonate is a saline cathartic, which increases intestinal peristalsis by osmotic properties. Docusate sodium is a stool... 

The duodenum and jejunum are capable of both absorption and secretion but absorption usually predominates. Regulation of intestinal secretion and absorption is highly complex and involves extrinsic and intrinsic neural stimuli, numerous receptor types and intercellular and intracellular transport pathways. Intracellular pathways of electrolyte transport involve membrane-associated receptors that activate cyclic nucleotide metabolism, membrane calcium channels and intracellular calcium metabolism, luminal and basal chloride channels and multiple sodium transport channels. Cholinergic stimuli tend to stimulate intestinal... 

Izzo A A, Mascolo N, Capasso F 1998 NO as a modulator of Intestinal water and electrolyte transport. Digestive Diseases and Sciences 43 1605-1620... 

Nath SK, Desjeux JP. Human intestinal cell hnes as in vitro tools for electrolyte transport studies with relevance to secretory diarrhoea. J Diarrhoea Dis Res 1990 Dec 8(4) 133-142. 

Beonnee F (1990) Intestinal calcium transport the cellular pathway. Miner Electrolyte Metab 16 94-100. 

Powell DW (1987) Intestinal Water and Electrolyte Transport. In Johnson LR, ed. Physiology of the Gastro Intestinal Tract, 2 ed. Raven Press, New York. 

DIARRHEA GENERAL PRINCIPLES AND APPROACH TO TREATMENT Diarrhea is defined as excessive fluid weight, with 200 g/day representing the upper limit of normal stool water weight for healthy adults. Since stool weight is largely determined by stool water, most cases of diarrhea result from disorders of intestinal water and electrolyte transport. 

Brown, D.R. and Miller, R.J. (1991) Neurohormonal control of fluid and electrolyte transport in intestinal mucosa, in Handout of Physiology, The Gastrointestinal System IV, Gastrointestinal Physiology Absorptive and Secretory Process of the Intestine, M. Field and R.A. Frizzel, Eds. pp. 527-589. Bethesda, MD American Physiological Society. 

Fig. 13.1. The transport of amino acids across the intestinal and tubular cells involves several steps, which are demonstrated schematically for a proximal tubular cell AAy amino acid BLMy basolateral membrane BBMy brush border membrane TBMy tubular basement membrane ly specific transporter at the luminal membrane 2, passive efflux from cytosol into tubular lumen 3, transport system at the basolateral membrane 4, transport from peritubular site into cytosol 5, energy production for electrolyte transport 5, passive efflux via paracellular gaps. (Taken from Foreman, JW and Segal, S (1987) Fanconi syndrome. In Pediatric Nephrology (eds. Holliday MA, Barratt TM and Vernier RC), pp 547-565, Williams and Wilkins, Baltimore, with permission to and modified by Brodehl J)...

WINGERTZAHN M A, TEICHBERG s, WAPNIR R A (2001) Stimulation of non-sodium-dependent water, electrolyte, and glucose transport in rat small intestine by gum arabic. DigDis Sci. 46 1105-12. 

V. cholerae is a gram-negative bacillus. Vibrios pass through the stomach to colonize the upper small intestine. Vibrios have filamentous protein extensions that attach to receptors on the intestinal mucosa, and their motility assists with penetration of the mucus layer.2 The cholera enterotoxin consists of two subunits, one of which (subunit A) is transported into the cells and causes an increase in cyclic AMP, which leads to a deluge of fluid into the small intestine.20 This large volume of fluid results in the watery diarrhea that is characteristic of cholera. The stools are an electrolyte-rich isotonic fluid, the loss of which results in blood volume depletion followed by low blood pressure and shock.2 Of note, the diarrheal fluid is highly infectious. 

Water and electrolytes. Each day in an average adult, about 5.51 of food and fluids move from the stomach to the small intestine as chyme. An additional 3.5 1 of pancreatic and intestinal secretions produce a total of 9 1 of material in the lumen. Most of this (>7.5 1) is absorbed from the small intestine. The absorption of nutrient molecules, which takes place primarily in the duodenum and jejunum, creates an osmotic gradient for the passive absorption of water. Sodium may be absorbed passively or actively. Passive absorption occurs when the electrochemical gradient favors the movement of Na+ between the absorptive cells through "leaky" tight junctions. Sodium is actively absorbed by way of transporters in the absorptive cell membrane. One type of transporter carries a Na+ ion and a Cl ion into the cell. Another carries a Na+ ion, a K+ ion, and two Cl ions into the cell. 

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