Transcellular fluid

The transcellular fluid includes the viscous components of the peritoneum, pleural space, and pericardium, as well as the cerebrospinal fluid, joint space fluid, and the gastrointestinal (GI) digestive juices. Although the transcellular fluid normally accounts for about 1% of TBW, this amount can increase significantly during various illnesses favoring fluid collection in one of these spaces (e.g., pleural effusions or ascites in the peritoneum). The accumulation of fluid in the transcellular space is often referred to as third spacing. To review the calculations of the body fluid compartments in a representative patient, see Patient Encounter 1. 

After absorption, the drug may be distributed into various body fluids like intestinal fluid, transcellular fluids e.g. fluids in the gastrointestinal tract, CSF etc. 

Transcellular fluid Fluid in the gastrointestinal (GI) tract, cerebrospinal space, aqueous humor, pleural space, synovial space, and the peritoneal space ° Plasma fluid... 

The unbound drug in the systemic circulation is available to distribute extravascularly. The extent of distribution is mainly determined by lipid solubility and, for weak organic acids and bases, is influenced by the pK3/pH-dependent degree of ionization because only the more lipid-soluble non-ionized form can passively diffuse through cell membranes and penetrate cellular barriers such as those which separate blood from transcellular fluids (cerebrospinal and synovial fluids and aqueous humour). The milk-to-plasma equilibrium concentration ratio of an antimicrobial agent provides a reasonably... 

Extracellular fluid contains sodium as the predominant cation and accounts for 20-25% of body weight, or one-third of total body water. It makes up vascular, interstitial, transcellular, and dense connective tissue fluid pools. Vascular fluid is the circulating portion, is rich in protein, and does not readily cross endothelial membranes. Interstitial fluid surrounds cells and accounts for 18-20% of total body water. It exchanges with vascular fluid via the lymph system. Transcellular fluid is present in digestive juices, intraocular fluid, cerebrospinal fluid (CSF),... 

Interstitial Transcellular fluid Cellular fluid fluid (ileal secretion)... 

The fluid spaces in the body occupy about 60% of the total body mass. The two main spaces are the intracellular fluid (ICF) and the extracellular fluid (ECF), with the ECF subdivided into the intravascular space (plasma), the interstitial space (lymph), and transcellular fluids such as pleural, cerebrospinal, pericardial, peritoneal, and gastrointestinal fluids. The ECF and ICF spaces are normally in an osmotic equilibrium in which body water moves under osmotic pressure between ICF and ECF, governed by the osmotically active molecules in each space. The electrolyte constituents of ICF and ECF are different, particularly for sodium, which is higher in ECF than ICF, and potassium, which is higher in ICF compared to ECF. 

Orally ingested salicylates are absorbed rapidly, predominantly from the upper small intestine. Appreciable concentrations are found in plasma in less than 30 minutes after a single dose, a peak value is reached in -1 hour and then declines gradually. After absorption, salicylates are distributed throughout most body tissues and transcellular fluids, primarily by pH-dependent passive processes. Salicylates are transported actively by a low-capacity, saturable system out of the cerebrospinal fluid (CSF) across the choroid plexus. The drugs readily cross the placental barrier. 

Extracellular fluid (ECF) is divided into smaller compartments. These spaces between the cells are called the interstitial space. The space is occupied by plasma and lymph, transcellular fluid, and fluid in the bone and connective tissues. This makes up 20% of body weight. About a third is plasma and two thirds of extracellular fluid is in the space between the cells. Transcellular fluid is also ECF but is found in the gastrointestinal (GI) tract, cerebrospinal space, aqueous humor, pleural space, synovial space, and the peritoneal space. Although fluid in the transcellular space is a small volume when compared with intracellular and extracellular compartments, the increase or decrease in volumes in transcellular spaces can have a dramatic effect on the fluid-electrolyte balance. 

Cross cell membranes very readily generally well absorbed from GIT in monogastric species penetrate into intracellular and transcellular fluids (e.g., synovial and prostatic fluids and bronchial secretions) also penetrate well into CSF, except tetracycbnes and rifampin termination of activity dependent on a high proportion of administered dose being metabobzed, for example, in the liver but also at other sites (e.g., kidney, enterocytes) some drugs actively secreted into bile... 

Sulfonamides are generally well distributed into extra-and transcellular fluids, but penetration into intracellular fluid is poor to moderate, a consequence of their acidic nature and the overall acid pH within cells. 

Transcellular fluid— includes all other fluids and represents 2 percent of body fluids (e.g., eye humors, spinal fluid, synovial fluid, and peritoneal, pericardial, pleural, and other fluids in the body)... 

Transcellular fluids may differ greatly in their pH values Gastric juice is very acidic (pH 1.5) the content of the small intestine is alkaline with a pH around 8 urine is usually slightly acidic with a pH of 5. Very few data are available about the pH of cells it is generally somewhat lower than that of extracellular fluids. 

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