Abstract
Studies using in vitro analysis have shown that the interaction between pulmonary surfactant and vernix caseosa could explain the appearance of amniotic fluid turbidity. That phenomenon is interpreted based on the “roll-up” hypothesis. We tested the roll-up hypothesis by examining the presence of micelles of pulmonary surfactant in human amniotic fluid at term. Amniotic fluid samples were collected from each of six healthy pregnant women at term and at 16 wk of gestation. These samples were stained negatively and analyzed using an electron microscope. Ultrastructures present in amniotic fluid were compared with the structure of micelles derived from suspended surfactant TA isolated from bovine lung. Surfactant TA formed spheroidal and rod-shaped micelles 10–70 nm in diameter above the critical micelle concentration. Identical micelle particles were described in human amniotic fluid at term. In addition, surfactant protein B was identified in the micelle fraction of amniotic fluid. However, no micelles were found in human amniotic fluid taken at 16 wk of gestation. Our results support the view that pulmonary surfactant could induce the detachment of vernix caseosa and increase the turbidity of the amniotic fluid.
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Abbreviations
- CMC:
-
critical micelle concentration;
- SP-B:
-
surfactant protein B.
References
Avery GB, Fletcher MA, MacDonald MG 1999 Neonatology: Pathophysiology and Management of the Newborn. 5th Ed. Lippincott Williams & Wilkins, Philadelphia, pp
Notter RH 2000 Lung Surfactants: Basic Science and Clinical Applications. Marcel Dekker, Inc., New York, pp
Hook GE, Gilmore LB, Tombropoulos EG, Fabro SE 1978 Fetal lung lamellar bodies in human amniotic fluid. Am Rev Respir Dis 117: 541–550
Agorastos T, Lamberti G, Vlassis G, Zournatzi B, Papaloucas A 1986 Methods of prenatal determination of fetal maturity based on differentiation of the fetal skin during the last weeks of pregnancy. Eur J Obstet Gynecol Reprod Biol 22: 29–40
Narendran V, Wickett RR, Pickens WL, Hoath SB 2000 Interaction between pulmonary surfactant and vernix: a potential mechanism for induction of amniotic fluid turbidity. Pediatr Res 48: 120–124
Kabin JA, Tolstedt SL, Saez AE, Grant CS, Carbonell RG 1998 Removal of organic films from rotating disks using aqueous solutions of nonionic surfactants: effect of surfactant molecular structure. J Colloid Interface Sci 206: 102–111
Lai K-Y, McCandlish EF, Aszman H 1996 Light duty liquid detergents. In Lai K-Y Liquid Detergents (Surfactant Series/67) Marcel Dekker Inc New York 207–259
Murray RK, Granner DK, Mayes PA, Rodwell VW 2000 Harper's Biochemistry. 25th Ed. Appleton & Lange, Stamford, Connecticut, pp
Fujiwara T, Maeta H, Chida S, Morita T, Watabe Y, Abe T 1980 Artificial surfactant therapy in hyaline-membrane disease. Lancet 1: 55–59
Tanaka Y, Takei T, Kanazawa Y, Seida K, Masuda K, Kiuchi A, Fujiwara T 1982 Preparation of surfactant from minced bovine lung, chemical composition and surface properties. J Jpn Med Soc Biol Interface 13: 87–94
Castro M, Ritacco H, Kovensky J, Fernandez-Cirelli A 2001 A simplified method for the determination of critical micelle concentration. J Chem Educ 78: 347–348
Ananthapadmanabhan KP, Goddard ED, Turro NJ, Kuo PL 1985 Fluorescence probes for critical micelle concentration. Langmuir 1: 352–355
Maggio B, Albert J, Yu RK 1988 Thermodynamic-geometric correlations for the morphology of self-assembled structures of glycosphingolipids and their mixtures with dipalmitoylphosphatidylcholine. Biochim Biophys Acta 945: 145–160
Dubertret B, Skourides P, Norris DJ, Noireaux V, Brivanlou AH, Libchaber A 2002 In vivo imaging of quantum dots encapsulated in phospholipid micelles. Science 298: 1759–1762
Glumoff V, Vayrynen O, Kangas T, Hallman M 2000 Degree of lung maturity determines the direction of the interleukin-1-induced effect on the expression of surfactant proteins. Am J Respir Cell Mol Biol 22: 280–288
Wright JR 1990 Clearance and recycling of pulmonary surfactant. Am J Physiol 259: L1–L12
Ross MG, Nijland MJ 1998 Development of ingestive behavior. Am J Physiol 274: R879–R893
Acknowledgements
The authors thank Hitoshi Takagi, Shintaro Nishijima, Mikiko Misawa, and Mari Ito for the excellent technical assistance.
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This work was supported in part by a Grant-in-Aid for Scientific Research No. 15659392 from the Ministry of Education, Culture, Sports, Science, and Technology, Japan. The sponsor had no role in the study design, data collection, data analysis, or writing of the report.
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Nishijima, K., Shukunami, KI., Tsukahara, H. et al. Micelles of Pulmonary Surfactant in Human Amniotic Fluid at Term. Pediatr Res 60, 196–199 (2006). https://doi.org/10.1203/01.pdr.0000228329.90502.3a
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DOI: https://doi.org/10.1203/01.pdr.0000228329.90502.3a
