Lymphatic system structure

For more detailed information on the respiratory tract, the pleura, and the lymphatic system, consult Gray s Anatomy or other standard medical texts. A comprehensive review of the lung and its structure and function is presented in Nagaishi (1972). 

There are four main compartments a soluble macromolecule can enter the central compartment (blood and lymphatic system), interstitium, intestinal lumen, and lysosomes [100, 101]. Minor compartments are primary urine, liquor, bile, etc. There is no experimental evidence that clearly indicates the penetration of synthetic macromolecules into the cytoplasm, i.e, into the intracellular compartment (inside the cell but outside the endosomes or lysosomes) [101]. The movements of soluble macromolecules between body compartments have been extensively reviewed [14, 20,100-104] and will not be covered in detail here. We shall concentrate on the discussion of main factors influencing the movement of soluble macromolecules when administered into the bloodstream. Depending on the structure and molecular weight distribution, part of the polymeric molecules are excreted in the urine. Simultaneously, the macromolecules are cleared from the bloodstream by endocytosis. It is important to note that nonspecific capture of soluble macromolecules by the specialized cells of the reticuloendothelial system is generally much less (orders of magnitude) when compared to vesicular carriers of a comparable structure. 

Gastrointestinal Tract Absorption. The structure and function of this tract is varied and complex. The structure of the pesticide may be altered within the G.I. tract due to changes in pH in the stomach and intestine, or due to enzymatic action within the gut before it is absorbed into the lacteals and eventually into the hepatic portal system or lymphatic system. 

Mutagenic carcinogenicity unknown caused birth defect and developmental abnormalities in blood and lymphatic systems in rats low toxicity in animals in humans, ingestion may cause paresthesias and affect the teeth and supporting structure LD50 oral (mice) 12,750 mg/kg. 

Many diversified activities of men and women are carried out through the combined actions of a complex structure of organ systems distributed in different parts of the human body. These include the musculoskeletal system, cardiovascular system, digestive system, endocrine system, integumentary system, lymphatic system, immune system, respiratory system, nervous system, urinary system, and reproductive system. 

The pleural tissue is a typical connective tissue that consists mostly of matrix the fibrous proteins (collagen, elastin), and mucopolysaccharides, and a few scattered mesothelial cells, capillaries, venules, and ducts. Anatomists have defined several layers (Fig. 3.4) for each of the pleura. Layers 3 and 5 in Fig. 3.4 contain an abundance of fibrous protein, especially elastin. Both the interstitial (Layer 4) and mesothelial (1 and 2) layers contain capillaries of the vascular system and lymphatic channels. The matrix (ground substance) gives the pleura structural integrity and is responsible for its mechanical properties such as elasticity and distensibility. 

Holm, R., Porter, C.J.H., Edwards, GA., Mullertz, A., Kristensen, H.G, and Charman, W.N. (2003) Examination of oral absorption and lymphatic transport of halofantrine in a tripie-cannulated canine model after administration in self-microemulsifying drug delivery systems (SMEDDS) containing structured triglycerides.Eur. J. Pharm. Sci., 20 91-97. 

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