Chloride intestinal absorption

Trospium chloride, a quaternary ammonium drug (Fig. 7.45), appears to be a substrate of P-gp, and it can be taken up by cells quicky [597]. The evidence for transmembrane diffusion appears substantial. The molecule is very soluble in water (>50 mg/mL), but not in lipids (9.2 pg/mL in mineral oil) the octanol-water log Kp is —1.22 [598]. The human intestinal absorption (HIA) is 11% the molecule is not metabolized. In cell intestinal patch uptake studies, trospium is absorbed from a... 

Thanou, M., Verhoef, J.C., Verheijden, J.H.M. and Junginger, H.E. (2001a) Intestinal absorption of octreotide using trimethyl chitosan chloride studies in pigs. Pharm. Res. 18 823-828. 

Treatment of Menkes patients have concentrated on restoring normal copper levels in the body by administering copper. Since the intestinal absorption of copper is very low in Menkes patients, copper must be administered parenteraUy. Copper has been administered in various forms including copper chloride, copper sulfate, copper EDTA, and copper-albumin. But none of these copper compounds is able to produce significant clinical improvement, especially in... 

Finally, it should be noted that during the last decade both weakly crosslinked poly(acrylic acid) derivatives and chitosan derivatives were described as safe penetration enhancers for hydrophilic compounds especially as they can trigger mechanisms of tight junction opening of mucosal tissues and did not show acute toxicity. Poly(acrylic acid) derivatives were shown to have excellent mucoadhesive properties and can inhibit the activity of gut enzymes, such as trypsin, chymo-trypsin, and carboxypepsidases. Chitosan salts and Ni-trimethylchitosan chloride revealed to be potential absorption enhancers for nasal absorption of calcitonin and insulin and for the intestinal absorption of buserilin.f ... 

In vitro evidence suggests that organic mercury is also readily absorbed in the gastrointestinal tract and that methylmercuric chloride is absorbed to a greater extent than phenylmercuric chloride (Endo et al. 1989). Complexing of methylmercury with nonprotein sulfhydryls also may play a role in intestinal absorption and reabsorption (Urano et al. 1990). Phenylmercuric salt in the diet was completely... 

Sips AJAM, van der Vijgh WJF, Barto R, et al. 1996. Intestinal absorption of strontium chloride in healthy volunteers Pharmacokinetics and reproducibility. Br J Clin Pharmacol 41 543-549. 

Thanou M, Verhoef JC, Marbach P, Junginger HE Intestinal absorption of octreotide N-trimethyl chitosan chloride (TMC) ameliorates the permeability and absorption properties of the somatostatin analogue in vitro and in vivo, J Pharm Sci 2000, 89, 951. 

An understanding of osmosis and the intestinal absorption of salt and glucose forms the basis for a simple therapy that saves millions of lives each year, particularly in less-developed countries. In these countries, cholera and other intestinal pathogens are major causes of death of young children. A toxin released by the bacteria activates chloride secretion by the intestinal epithelial cells into the lumen water follows osmotlcally, and the resultant massive loss of water causes diarrhea, dehydration, and ultimately death. A cure demands not only killing the bacteria with antibiotics, but also rehydration— replacement of the water that is lost from the blood and other tissues. 

Strontium-90 Alginate or aluminum hydroxide-containing antacids may reduce intestinal absorption of strontium. Dose 10 g, then 1 g 4 times daily. Barium sulfate may also reduce Sr absorption. Dose 100 g in 250 mL water PO. Calcium gluconate may dilute the effect of strontium. Dose 2 g in 500 mL PO or IV. Ammonium chloride is a demineralizing agent. Dose 3 g PO 3 times daily. 

Chloride (Cl") Intestinal absorption Renal reabsorption Renal excretion... 

Figure 14 Ion transport pathways responsible for water flux across intestinal epithelia. Sodium absorption in villus tip cells (left) stimulates water absorption, while chloride channel exit in crypt cells (right) stimulates water secretion.

Although infection with C. parvum is considered predominantly secretory, histopathologic studies have revealed varying degrees of villous atrophy and infiltration of inflammatory cells beneath the epithelial mucosa [85, 86], Prostaglandins, which are known to induce cAMP-mediated apical chloride secretion and inhibit electroneutral sodium chloride and water absorption in enterocytes, have been demonstrated to be elevated in a porcine model of cryptosporidiosis [87], Inflammatory cytokines such as IL-1, IL-8 and TNF-a are induced in intestinal epithelial cell lines infected with Cryptosporidium and in animal models of cryptosporidiosis and have been postulated to play a role in pathogenesis [88, 89], Expression of TNF-a and IL-1 mRNA in the majority of jejunal biopsies of adult volunteers after experimental infection were also observed, although this did not correlate with the enteric symptoms [90]. 

Most pathology of cholera is thought to result from an enterotoxin that increases cyclic adenosine monophosphate-mediated secretion of chloride ion into the intestinal lumen, which results in isotonic secretion (primarily in the small intestine) exceeding the absorptive capacity of the intestinal tract (primarily the colon). 

With an increase in pH, there is an increased absorption of mercuric chloride [6, 7], whereas accumulation of mercury in the intestinal tissue decreases. Mercury absorption is inversely proportional to its accumulation in the tissue. An increase in water absorption due to hypotonicity or an increase in concentration of sodium ions or urea increases the mercury absorption and accumulation in the epithelial cell, without change in the intracellular distribution pattern [8], Thus, the absorption of mercury is thought to accompany the solvent drag and to be influenced by pH change in the intestinal lumen. 

---