Surface Tension Lowering Substance Research Articles

サーファクタント様物質と滲出性中耳炎(総説)

The cause of OME (otitis media with effusion) is not clearly known, but many studies indicate that dysfunction of the eustachian tube plays a role in its pathogenesis. The potential existence of a STLS (surface tension lowering substance) in the middle ear cavity which facilitates the opening of the eustachian tube was first postulated by Bauer in 1970.Appreciable phospholipids were shown to be present in eustachian tube lavage fluid by many investigators. The major components of pulmonary surfactant are phospholipids, especially DSPC (dipalmitoyl phosphatidylcholine). We also detected the existence of DSPC in middle ear effusions.Monoclonal antibodies against pulmonary surfactant protein were prepared by Kuroki et al. We found fine positive granules in the mucosal epithelial cells of the middle ear, while Lamellar bodies were found in the secretory cells of the middle ear by electromicroscopic examinations.Yamanaka et al reported that the positivity of SAP (surfactant apoprotein) in middle ear effusions showed a good correlation with the clinical course of OME, and the period of observation of SAP-positive cases being significantly shorter than that of SAP-negative cases.Some investigators have suggested the efficacy of treating OME with artificial pulmonary surfactant. Kobayashi et al reported that the use of artificial surfactant was effective for patients with OME.

Role of surface tension lowering substances in the function of normal and diseased eustachian tubes of guinea pigs

To examine the role of surface tension lowering substances (STLSs), we measured changes in passive opening pressure (OP) and closing pressure (CP) in eustachian tubes of guinea pigs before and after washing the tubes with various solutions (saline solution, artificial pulmonary surfactant, synthetic phospholipids, and detergent)). The percent decreases in OP and CP in tubes washed with artificial surfactant were significantly higher than those washed with saline solution. Those washed with synthetic phospholipids or detergent (Triton X-100) did not differ from those washed with saline solution. In guinea pigs with experimental otitis media produced by inoculation of formalin-killed Haemophilus influenzae into the middle ear cavity, the percent decreases in OP and CP in tubes washed with artificial pulmonary surfactant were significantly higher than in those washed with saline solution. Artificial pulmonary surfactant was injected into the middle ear cavity of the guinea pigs with otitis media. At 5 days after inoculation, the inflammatory changes of the middle ear were much milder in animals with intratemporal application of artificial pulmonary surfactant than in those with saline application. These results suggest the possible efficacy of treatment with artificial pulmonary surfactant for otitis media.

Surfactant and isoprenaline effect on eustachian tube opening in rats with acute otitis media

Purulent otitis media was induced in 12 middle ears of Sprague-Dawley rats by inoculation of pneumococci type 3. The pressure required to open the eustachian tube was recorded 4 days later and was found to be 3.05 ± 0.10 kPa (mean ± SEM), which was 1.08 ± 0.15 kPa lower than the mean value obtained in a control group of healthy rats ( P ⩽ .001). We also measured the effects of pulmonary surfactant instilled into the middle ear as well as isoprenaline injected intravenously. The presence of surfactant further reduced the pressure opening level by 0.72 ± 0.05 kPa; this reduction did not differ from that found in the control group ( P > .8). Isoprenaline reduced the pressure opening level in the control group by 0.20 ± 0.03 kPa ( P ⩽ .001), and no reduction was found in the rats with otitis media. Although the part played by surface tension-lowering factors in eustachian tube function is still uncertain, such factors apparently also exert an effect in the inflamed tube. However, isoprenaline, which is considered to act by the secretion of surface tension-lowering substances, did not facilitate opening of the eustachian tube in rats with acute otitis media.

Effect of exogenous surfactant on eustachian tube function in the rat

Three solutions, surfactant prepared from pig lungs, a mixture of synthetic phospholipids, and saline solution, were instilled into the middle ears of rats. The middle ear pressure necessary to force the eustachian tube open was studied. Ten minutes after instillation of pulmonary surfactant there was a 0.58 ± 0.10 kPa decrease in the pressure opening level ( P < .001). The reduction persisted throughout the 50-minute experiment. There was also a reduction 0.17 ± 0.16 kPa in the pressure opening level ( P < .01) after the administration of the synthetic phospholipid mixture. This reduction was significantly less than the reduction produced by the pulmonary surfactant. No decrease in the pressure opening level was seen after the instillation of saline solution into the middle ear cavity. The fact that surfactants are demonstrable in the middle ear and eustachian tube, coupled with these findings of an effect on the tubal opening, suggests a physiologic role for surface tensionlowering substances in tubal function.

Effect of terbutaline on human eustachian tube function.

Terbutaline, a beta 2-adrenoceptor agonist, was administered subcutaneously to 10 healthy adult subjects. The pressure opening level (Pol) of the Eustachian tube (ET) and the remaining middle ear pressure when the ET closed (Pcl) after passive equilibration were measured as well as parameters for active tubal function. A quantitative impedance method in combination with a pressure chamber was used. Pol was reduced by 0.29 +/- 0.10 (-7.3%) kPa 90 min after injection of terbutaline 5 micrograms/kg body weight. There was also a decrease in Pcl, 0.17 +/- 0.06 kPa (-14.0%). No such decrease was seen after saline solution injected subcutaneously. It is suggested that terbutaline facilitates the ET opening by stimulating the secretion of surface tension lowering substances.

The influence of pregnancy on the eustachian tube function in rats.

Textbooks of otorhinolaryngology usually report that one-third of women diagnosed for patulous Eustachian tube (tuba aperta) are pregnant or on estrogenic therapy. To investigate whether the opening of the Eustachian tube (ET) can be facilitated experimentally during pregnancy, the ET opening function of 14 pregnant rats was compared with that of 14 nonpregnant controls. The air pressure at which the ET opened (the pressure opening level, Pol) when air is injected into the middle ear, and the pressures maintaining open ET during continued air injection were measured. The Pol was lower in the pregnant rats, whereas there was no difference in pressures between the two groups during open ET. The differences between Pol and the pressures during open ET were smaller in the pregnant rats than in the controls. It was furthermore demonstrated in 2 rats that, after instillation of a surface tension lowering substance in the middle ear, the Pol was reduced markedly, whereas the effect on the pressure during open ET was less pronounced. It is concluded that pregnancy facilitates opening of the ET in rats and it is suggested that it is done by reducing the surface tension of the ET secretion.

Rat eustachian tube synthesizes disaturated phosphatidylcholine

Otitis media results when the eustachian tube fails to adequately ventilate the middle ear. A surface tension-lowering substance may be required for normal tube opening, especially in young children with poorly developed naso-pharyngeal musculature. We report here that rat eustachian tube epithelium synthesizes disaturated phosphatidylcholine, which is recognized as the surface tension-lowering substance of pulmonary surfactant.

Isoprenaline-induced facilitation of the Eustachian tube opening.

Isoprenaline was given i.v. to rats and its ability to change the air pressure necessary to open the Eustachian tube (ET) was studied. Air was injected once a minute into the middle ear via a tube glued to a hole in the tympanic bulla. The rate of pressure increase was 0.7 kPa/sec. The air pressure at which the ET opened was in 10 rats 3.4 +/- 0.3 (SE) kPa. Isoprenaline in a dose of 1 microgram/kg decreased this pressure opening level (Pol) by 0.14 +/- 0.03 kPa and with 10 micrograms/kg by 0.22 +/- 0.03 kPa. These effects were reduced by propranolol. Isoprenaline did not act via released adrenaline. A surface tension lowering substance, Tween 20, instilled into the middle ear, decreased Pol by about 0.9 kPa. It is suggested that isoprenaline evokes a decreased Pol via secretion of surface tension lowering substances.

Surface tension lowering substance in Eustachian tube function.

AbstractDirect evidence is presented that establishes the existence of an Eusta‐chian tube surface tension lowering substance (S.T.L.S.) in the canine experimental model. The physiological role of this Eustachian tube S.T.L.S. is to facilitate middle ear ventilation by lowering the opening pressure needed to aerate the Eustachian tube and middle ear. While S.T.L.S. possesses characteristics similar to those of the pulmonary surfactant, experimental data suggest that it does not reduce the surface tension in the auditory conduit of the middle ear to the degree that the surfactant does in pulmonary system. Neither does Eustachian S.T.L.S. exhibit the physical characteristic of “hysteresis” that the alveolar surfactant demonstrates.The paper presents brief discussion of the physical phenomenon of surface tension as it exists in the Eustachian tube. Various methods of physical surface chemistry used in measuring the surface pressure of the canine Eustachian S.T.L.S. extract are discussed, including criticism of the indirect methodology of previous researchers in investigating the possibility of an Eustachian tube S.T.L.S. Direct methodology, utilizing the Langmuir Trough with Wilhelmy surface balance, was employed.S.T.L.S. is considered in its physiologic role in maintaining Eustachian tube patency. It is suggested that a decreased amount of Eustachian S.T.L.S. may be implicated in the pathophysiology of the serous acellular sterile middle ear transudate in serous otitis media. Finally, it is stressed that this preliminary work needs further histochemical and physiological investigation.

Lamellated bodies in the normal paranasal sinus mucosa. Transmission electron microscope observation.

Paranasal sinus disease is still an enigma in otolaryngology unfortunately little being achieved to solve the problem. The pluricausal aetiology requires further research of basic pathophysiololog ical principles. Histological studies are numerous, but compared to the middle ear pathology ultrastructural investigations are very scattered. Introducing the objective sinumanometry as a paranasal ostium function test we are able to determe the ostium resistance before and after saline irrigation of the sinus [6]. The discrepancy of the two datas gave rise to the speculation of the existence of a surface tension lowering substance in sinus secretion similiar to the lung and the middle ear. This assumption was underlined by biochemical analysis yielding high Dipalmitoyllezit hin concentration in human sinus secretions (Bauer and Mann, unpublished data). These findings were the incitement for further ultrastructural morphological studies of human sinus mucosa. Material and Methods

Etiologic factors in non-suppurative otitis media.

Two observations in non-suppurative otitis media, namely the serous fluid and the tympanic membrane retraction, may have separate explanations as to the etiologic factors. The first is the obstruction of the collecting lymphatic tubules of the middle ear and eustachian tube as they drain to the retropharyngeal lymphatics. This leads to a transudation of fluid in the middle ear or serous fluid. The second observation, retraction of the tympanic membrane, may be due to an absence or significant reduction of the surface tension lowering substance (Surface Active Membrane) of the eustachian tube, preventing the transmission of air to the middle ear from the nasopharynx.

Surface tension lowering substance of the Eustachian tube in non-suppurative otitis media: an experiment with dogs.

AbstractA surface tension lowering substance (STLS) lining the Eustachian tube was recently identified. STLS was Postulated to prevent the adherence of the tubal surface and allow for the facile opening by the tubal musculature.In Order to determie the role of STLS, non‐suppurative otitis media was produced in dogs by injecting polytetrafluoethylene paste immediately posterior to the torus tubarius. The presence of STLS was ascertained and found not to be diminished by experimentally produced non‐suppurative otitis media; however, in one case, purulent otitis media was produced, and STLS was absent. This situtation was analogous to teh fate of STLS of the lung (surfactant) during pneumonia.The possible causes for these observed results were postulated. The role of STLS in Eustachian tubal function was delineated.

Surface tension lowering substance of the eustachian tube.

The LaryngoscopeVolume 81, Issue 10 p. 1671-1673 Article Surface tension lowering substance of the eustachian tube†‡ Kenneth H. Brookler M.D, Kenneth H. Brookler M.D New York, N. Y.Search for more papers by this authorEric A. Birken M.D, Eric A. Birken M.D New York, N. Y.Search for more papers by this author Kenneth H. Brookler M.D, Kenneth H. Brookler M.D New York, N. Y.Search for more papers by this authorEric A. Birken M.D, Eric A. Birken M.D New York, N. Y.Search for more papers by this author First published: October 1971 https://doi.org/10.1288/00005537-197110000-00014Citations: 6 † Presented at the 74th Annual Meeting of the American Laryngological, Rhinological and Otological Society, Inc., San Francisco, Calif., May 27, 1971. ‡ Research supported in part by a Grant from the Deafness Research Foundation. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume81, Issue10October 1971Pages 1671-1673 RelatedInformation

Physical Factors in the Thromboplastic Activity of Phospholipids

SummaryCephalin suspensions lose their thromboplastic activity when incubated with Tween or with sodium deoxycholate. This effect is proportional to the concentration of the surface-active substance, and to the length of its incubation with the phospholipids.The disappearance of the thromboplastic activity of cephalin treated with surface-tension lowering substances is due to the increased dispersion of the suspensions, as demonstrated by the decrease of their optical density. The activity of sodium deoxycholate is faster than that of Tween.The impaired thromboplastin formation in the presence of phospholipids treated with Tween or with sodium deoxycholate is not due to the formation of inhibitors.Cephalin incubated with surface-tension lowering substances and recovered by ultracentrifugation does not show any thromboplastic activity.Electron-microscopic studies show that incubation with surface-active substances causes the demolition of the structure of phospholipid-particle, on which the thromboplastic activity seems to depend.The size of the particles and the electric surface-charge seem to be among the main factors responsible for the thromboplastic activity of phospholipids.

Effects of Triethanolamine on Hemolysis.

The author's previous work on the surface tension lowering substance, sodium taurocholate, and its effects on red blood cells as demonstrated by hemolysis suggested like observations on triethanolamine, N (C2H4OH)3, a new surface tension lowering compound now used commercially as an emulsifying agent and superior to similar agents previously used because of its low alkalinity, ability to cause finer and more stable dispersions, its slightly bactericidal powers, etc. Approximately 25 human bloods were examined, a drop of blood drawn from the patient by syringe being added directly to each tube containing 2 cc. of the solution to be observed. Varying dilutions of sodium chloride, potassium chloride, calcium chloride, sodium hydroxide, hydrochloric acid, acetone, saponin, sodium taurocholate, venom from the bothrops atrox and sulphanilic acid were observed for hemolysis as such and containing 5% triethanolamine and the results compared. The influence of triethanolamine on the pH of the solutions and the time of hemolysis were also noted. The first readings registered were taken 2 hours after the addition of the blood. Normal sodium chloride was used as a vehicle with the exception of the sodium, potassium and calcium chloride dilutions and where otherwise noted. The pH of the distilled water and normal sodium chloride ranged from 5.6-5.8. In the case of the sodium chloride dilutions, hemolysis began at the .40% concentration of the salt without triethanolamine and at the .30% concentration with the triethanolamine, the triethanolamine in each case definitely increasing the alkalinity of the solutions. Similar results were obtained with the potassium and calcium chlorides.