Pulmonary surfactants

Johansson, J., Szyperski, T, Curstedt, T., and Wuthrich, K. The NMR structure of the pulmonary surfactant-associated polypeptide SP-C in an apolar solvent contains a valyl-rich alpha-helix. Biochemistry 1994, 33, 6015-6023. 

Collagen, the major component of most connective tissues, constimtes approximately 25% of the protein of mammals. It provides an extracellular framework for all metazoan animals and exists in virmally every animal tissue. At least 19 distinct types of collagen made up of 30 distinct polypeptide chains (each encoded by a separate gene) have been identified in human tissues. Although several of these are present only in small proportions, they may play important roles in determining the physical properties of specific tissues. In addition, a number of proteins (eg, the Clq component of the complement system, pulmonary surfactant proteins SP-A and SP-D) that are not classified as collagens have... 

Le Mesurier SM, Lykke AW, Stewart BW. 1980. Reduced deld of pulmonary surfactant Patterns of response following administration of chemicals to rats by inhalation. Toxicol Lett 5 89-93. 

Biinger, H., Kaufner, L., and Pison, U., Quantitative analysis of hydrophobic pulmonary surfactant proteins by high-performance liquid chromatography with light-scattering detection, /. Chromatogr. A, 870, 363, 2000. 

Kay, K. (1970) Pesticides and associated health factors in agricultural environments effects on mixed-function oxiding enzyme metabolism, pulmonary surfactant and immunological reactions, in Pesticides Symposia, R. Dichmann (Ed.), Halos Co., Miami, FL. 

Normal lungs, however, produce a chemical substance referred to as pulmonary surfactant. Made by alveolar type II cells within the alveoli, surfactant is a complex mixture of proteins (10 to 15%) and phospholipids (85 to 90%), including dipalmitoyl phosphatidyl choline, the predominant constituent. By interspersing throughout the fluid lining the alveoli, surfactant disrupts the cohesive forces between the water molecules. As a result, pulmonary surfactant has three major functions ... 

Pulmonary surfactant decreases surface tension of alveolar fluid. Reduced surface tension leads to a decrease in the collapsing pressure of the alveoli, an increase in pulmonary compliance (less elastic recoil), and a decrease in the work required to inflate the lungs with each breath. Also, pulmonary surfactant promotes the stability of the alveoli. Because the surface tension is reduced, the tendency for small alveoli to empty into larger ones is decreased (see Figure 17.2, panel b). Finally, surfactant inhibits the transudation cf fluid out of the pulmonary capillaries into the alveoli. Excessive surface tension would tend to reduce the hydrostatic pressure in the tissue outside the capillaries. As a result, capillary filtration would be promoted. The movement of water out of the capillaries may result in interstitial edema formation and excess fluid in the alveoli. 

Infant respiratory distress syndrome (IRDS), also known as hyaline membrane disease, is one of the most common causes of respiratory disease in premature infants. In fact, it occurs in 30,000 to 50,000 newborns per year in the U.S. — most commonly in neonates bom before week 25 of gestation. IRDS is characterized by areas of atelectasis, hemorrhagic edema, and the formation of hyaline membranes within the alveoli. IRDS is caused by a deficiency of pulmonary surfactant. Alveolar type II cells, which produce surfactant, do not begin to mature until weeks 25 to 28 of... 

The therapy for IRDS includes mechanical ventilation with continuous positive airway pressure. This maintains adequate ventilation and prevents airway collapse between breaths with the formation of atelectasis. Therapy also includes administration of exogenous pulmonary surfactant. Two types of surfactants are used to prevent and treat IRDS in the U.S. These include surfactants prepared from animal sources as well as synthetic surfactants. Exogenous pulmonary surfactants are administered as a suspension (in saline) through the endotracheal tube used for mechanical ventilation. 

Frosolono and Currie (1985) investigated the effect of phosgene on the pulmonary surfactant-system (PSS) in groups of six to 14 rats exposed to phosgene at 1 ppm for 4 h. The exposure system and parameters were similar to those described in Section 3.2.1 (Hatch et al. 1986). The actual chamber concentration was 1.0 0.06 ppm. Animals were sacrificed immediately after exposure, or on postexposure days 1, 2, or 3. Pulmonary edema was present immediately after exposure and persisted through day 3. Phosphatidylinositol levels were significantly (p<0.05) decreased compared with controls immediately after exposure only. Phosphatidylserine and phosphatidylethanolamine levels were significantly increased compared with controls on days 1, 2, and 3 postexposure. Phosphatidylcholine levels were increased at all time points compared with controls. 

Frosolono, M.F. and Currie, W.D. 1985. Response of the pulmonary surfactant system to phosgene. Toxicol. Ind. Health. 1 29-35. 

PSPD HUMAN P35247 PULMONARY SURFACTANT-ASSOCIATED PROTEIN... 

Varit Veen A, Gommers D, Verbrugge SJC, Wollmer P, Mouton JW, Kooij PPM, Lachmann B (1999) Lung clearance of intratracheally instilled Tc-99m-tobramycin using pulmonary surfactant as vehicle. Br J Pharmacol 126 1091-1096. 

Van t Veen A, Mouton JW, Gommers D, Kluytmans JAJ, Dekkers P, Lachmann B (1995) Influence of pulmonary surfactant on in vitro bactericidal activities of amoxicillin, ceftazidime, and tobramycin. Antimicrob Agents Chemother 39 329-333. 

Takahashi H, Sano H, Chiba H, Kuroki Y (2006) Pulmonary surfactant proteins A and D innate immune functions and biomarkers for lung diseases. Curr Pharm Des 12(5) 589-598... 

Duncan JE, Whitsett JA, Horowitz AD (1997) Pulmonary surfactant inhibits cationic liposome-mediated gene delivery to respiratory epithelial cells in vitro. Hum Gene Ther 8(4) 431-438... 

Ectopeptidases of the alveolar epithelium are also involved in the regulation of pulmonary surfactants [24], The cell-surface enzymes on monocyte-... 

Patthy L. Homology of the precursor of pulmonary surfactant-associated protein SP-B with prosaposin and sulfated glycoprotein 1. J Biol Chem 1991 266(10) 6035-6037. 

Andersson M. An amphipathic helical motif common to tumourolytic polypeptide NK-lysin and pulmonary surfactant polypeptide SP-B. FEBS Lett 1995 362(3) 328-332. 

Shiffer K, Hawgood S, Duzgunes N, et al. Interactions of the low molecular weight group of surfactant-associated proteins (SP 5-18) with pulmonary surfactant lipids. Biochemistry 1988 27(8) 2689-2695. 

Respiratory effects are more likely to occur after inhalation exposure to high concentrations of chloroform. It has been demonstrated that chloroform has a destructive influence on the pulmonary surfactant (Enhoming et al. 1986). This effect is probably due to the solubility of phospholipids in the surfactant monolayer and can cause collapse of the respiratory bronchiole due to the sudden increase in inhalation tension. Immediate death after chloroform inhalation may be due principally to this effect in the lungs (Fagan et al. 1977). It is unlikely that exposure levels of chloroform in the general environment or at hazardous waste sites would be high enough to cause these severe respiratory effects. 

Enhoming G, Potoschnik R, Possmayer F, et al. 1986. Pulmonary surfactant films affected by solvent vapors. Anesth Analg 65 1275-1280. 

GiammonaST. 1967. Effects of furniture polish on pulmonary surfactant. Am J Dis Child 113 658-663. 

T e II cells (granular pneumonocytes) are distributed throughout the alveoli between T e I cells. Although they are more numerous than T e I cells, they are cuboidal in shape and occupy far less of the alveolar surface area. The prime function of this cell is the production of pulmonary surfactant, and it is generally less susceptible to injury than the Type I cell. 

Ma LY, LaCagnin LB, Bowman L, et al. 1989. Carbon tetrachloride inhibits synthesis of pulmonary surfactant disaturated phosphatidylcholines and ATP production in alveolar type II cells. Acta Biochem Biophys 1003 136-144. 

G. Gairola. Biochemical and biophysical characterization of pulmonary surfactant in rats exposed chronically to cigarette smoke. Fundam Appl Toxicol 1995 27(1) 63-69. 

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