Mucus-depleted frog palate as a model for the study of mucociliary clearance

To better understand the frog palate model of mucociliary transport, we measured the transport rate of mucus (MTR) from the leopard frog, Rana pipiens, and from the bullfrog, R. catesbeiana, recorded the stability of the MTR over a period of hours and days and over the course of 1 yr, and measured the viscoelasticity, percent solid composition, and spinnability (filance) of mucus from both species. Bullfrog mucus was less rigid than leopard frog mucus (log G* at 1 rad/s 2.09 vs. 2.61; P less than 0.01) and had a higher viscosity-to-elasticity ratio (tan delta at 1 rad/s 0.36 vs. 0.26; P less than 0.05). It also had a lower solids content (8.71 vs. 13.72%; P = 0.02), and there was a trend to lower spinnability for bullfrog mucus (filance 26.7 vs. 33.5 mm). These data suggest that bullfrog mucus has viscoelastic properties similar to normal mammalian respiratory mucus and leopard frog mucus has viscoelasticity similar to sputum samples. MTR was significantly slower in the winter than in the summer months (17 vs. 30 mm/min; P less than 0.0001). Although the leopard frog palate could be used for at least 7 consecutive days without exhaustion, bullfrog palates could be used for only 5 days. Palates of either species could generally be tested for 6 h/day without a significant decrease in MTR. These data clarify some of the sources of variability in the use of this system and suggest methods of standardization.

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Is there a seasonal variation in mucus transport and nutrient absorption in the leopard frog?

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y92-056 ◽

1992 ◽

Vol 70 (4) ◽

pp. 442-446 ◽

Cited By ~ 1

Author(s):

Bruce K. Rubin ◽

Chris I. Cheeseman ◽

Sita Gourishankar ◽

Malcolm King

Keyword(s):

Seasonal Variation ◽

Seasonal Variability ◽

Rana Pipiens ◽

Mucociliary Clearance ◽

Intestinal Transport ◽

Leopard Frog ◽

Intestinal Lumen ◽

Leopard Frogs ◽

Different Seasons ◽

Frog Palate

We postulated that as a hibernating species, frogs might have variable demands for nutrients at different seasons of the year and that this must be reflected in seasonal variations of physiologic processes related to nutrient transport and absorption. We examined the rate of mucus transport on the ciliated palate and the movement of nutrients across the intestinal lumen of leopard frogs, Rana pipiens. Mucus transport on the frog palate was strongly influenced by season, with maximal transport occurring in late June (Julian day 178, p = 0.0001; r = 0.58). This increased transport rate was associated with a summertime increase in mucus recoil (lower tangent δ) and a decrease in mucus hydration (increase in percent solids composition). Intestinal transport of leucine, lysine, and galactose did not appear to exhibit seasonal variability. These data suggest that different mechanisms may operate in determining seasonal variability in physiologic responses.Key words: mucociliary clearance, mucus viscoelasticity, intestinal absorption, Anura, seasonal variation.

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Mucociliary Transport Function and Damage of Ciliated Epithelium

American Journal of Rhinology ◽

10.1177/194589240201600407 ◽

2002 ◽

Vol 16 (4) ◽

pp. 215-219 ◽

Cited By ~ 5

Author(s):

Tian-qun Yang ◽

Yuichi Majima ◽

Yongqing Guo ◽

Teruhiko Harada ◽

Takeshi Shimizu ◽

...

Keyword(s):

Mucosal Damage ◽

Transport Rate ◽

Ciliated Epithelium ◽

Mucociliary Transport ◽

Transport Function ◽

Plastic Plate ◽

Mucosal Epithelium ◽

Epithelial Damage ◽

Frog Palate ◽

Different Thickness

The influence of epithelial damage on mucociliary transport was studied in relation to the amount of mucus. The mucosal epithelium of mucus-depleted frog palate was dissected and mounted on a plastic plate. Mechanical damages were created on the frog mucosa by pressing a different thickness of boards (2, 3, 5, and 8 mm). Two different amounts of frog mucus (7.9 L [small amount of mucus {S-mucus}]) and 51.0 L [large amount of mucus {L-mucus}])were applied on the frog mucosa with and without mucosal damage. There was no difference in mucociliary transport rate (MTR) on undamaged frog mucosa between S-mucus and L-mucus. However, on the damaged mucosa, MTR of S-mucus was significantly decreased compared with that of L-mucus. Moreover, capability of mucus transportation across the mucosal damage was significantly lower in S-mucus than in L-mucus. Results indicate that the larger the mucus amount becomes, the more the mucus travels the damaged epithelium. Moreover, MTR of L-mucus was decreased with increasing the degree of epithelial damage. This study indicates that the degree of loss of cilia is an important factor of mucociliary deceleration. (American Journal of Rhinology 16, 215–219, 2002)

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Rheologic and Transport Properties of Middle Ear Effusions from Cleft Palate Patients

Otolaryngology ◽

10.1177/019459987808600215 ◽

1978 ◽

Vol 86 (2) ◽

pp. ORL-269-ORL-275 ◽

Cited By ~ 1

Author(s):

Bruce J. Romanczuk ◽

William P. Potsic ◽

Allan L. McCall ◽

Mohammad A. Khan ◽

Chung K. Shih ◽

...

Keyword(s):

Cleft Palate ◽

Transport Properties ◽

Middle Ear ◽

Viscoelastic Properties ◽

Transport Rate ◽

Transport Systems ◽

Mucociliary Transport ◽

Transport Defect ◽

The Relationship ◽

Serous Otitis Media

Middle ear effusions represent respiratory secretions which are physiologically important to functional mucociliary transport systems. Knowledge of middle ear mucus and methods of facilitating clearance continue to be important to cleft palate patients. Middle ear mucus was collected from the ears of children with cleft palate before surgical correction. Samples were dialyzed and lyophilized to yield mucus powder. This mucus was reconstituted at various nondialyzable solids (NDS) concentrations in TRIS-CI buffer. A physiochemical study of the middle ear mucus was then undertaken, since a mucociliary transport defect leading to serous otitis media (SOM) is an etiologic possibility. The viscoelastic properties of reconstituted middle ear mucus of cleft palate children were determined using a magnetic microrheometer. The relationship to nondialyzable solids concentrations is also described. The mucociliary transport rate as a function of NDS concentrations was recorded on the toad palate model. Results suggest a maximum transport rate at a specific NDS concentration. The viscoelastic properties also correlate well with the mucociliary transport rate. These may have clinical and therapeutic relevance.

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Preliminary Data on the Action of Nesosteine, a Mucomodifying Drug, on Mucociliary Transport

Journal of International Medical Research ◽

10.1177/030006058701500107 ◽

1987 ◽

Vol 15 (1) ◽

pp. 57-61 ◽

Cited By ~ 4

Author(s):

P. C. Braga ◽

R. Bossi ◽

C. L. Castiglioni ◽

S. Romandini ◽

L. Allegra

Keyword(s):

Oral Administration ◽

Chronic Bronchitis ◽

Preliminary Data ◽

Mucociliary Clearance ◽

Mucociliary Transport ◽

Relative Speed ◽

End Of Treatment ◽

Acute Exacerbations ◽

Before And After ◽

Frog Palate

Nesosteine, which is active on airway secretions, has been studied by assessment of the mucociliary clearance of the frog palate. Sputum was collected from patients admitted to hospital with acute exacerbations of chronic bronchitis with mucous expectoration. The relative speed of transport was measured for each patient before and after oral administration of 600mg/day nesosteine. A significant increase in the mucus transport rate was found at the end of treatment

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Comparison of Nasal and Bronchial Mucociliary Clearance in Young Non-Smokers

Clinical Science ◽

10.1042/cs0620013 ◽

1982 ◽

Vol 62 (1) ◽

pp. 13-16 ◽

Cited By ~ 12

Author(s):

Edith Puchelle ◽

F. Aug ◽

J. M. Zahm ◽

A. Bertrand

Keyword(s):

Nasal Mucosa ◽

Particle Deposition ◽

Inverse Relationship ◽

Mucociliary Clearance ◽

Central Zone ◽

Transport Rate ◽

Mucociliary Transport ◽

Initial Particle ◽

Total Deposition ◽

Initial Deposition

1. Nasal and bronchial mucociliary clearance have been studied in ten non-smokers (aged 19–23 years). Nasal mucociliary transport was evaluated by measuring the transport rate of a single radioactive (99mTc) particle deposited on the nasal mucosa. Bronchial clearance was measured after inhalation of insoluble radioactive anionic particles (diameter 7.4 ± 1.5 μm). The initial deposition of the aerosol and subsequent clearance over 1 h was monitored with a γ-camera 2. The initial particle deposition was concentrated centrally and was similar in all subjects. The percentage of the total deposition located in the central zone was 78.2 ± 5.8. The range for nasal transport rate (0–12.6 mm/min) and bronchial mucociliary clearance (18.1–77.0%) was large 3. An inverse relationship (rs = −0.63, P < 0.05) was observed between nasal transport rate and bronchial clearance, suggesting that, in young non-smokers, the lower the rate of the nasal mucociliary transport the faster the bronchial mucociliary clearance.

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